diff --git a/xml/System.Collections.Immutable/ImmutableArray.xml b/xml/System.Collections.Immutable/ImmutableArray.xml
index 9745ec29ff4..91785a73896 100644
--- a/xml/System.Collections.Immutable/ImmutableArray.xml
+++ b/xml/System.Collections.Immutable/ImmutableArray.xml
@@ -679,12 +679,12 @@ This overload allows helper methods or custom builder classes to efficiently avo
         <Parameter Name="selector" Type="System.Func&lt;TSource,TResult&gt;" />
       </Parameters>
       <Docs>
-        <typeparam name="TSource">To be added.</typeparam>
-        <typeparam name="TResult">To be added.</typeparam>
+        <typeparam name="TSource">The type of element stored in the source array.</typeparam>
+        <typeparam name="TResult">The type of element to store in the target array.</typeparam>
         <param name="items">The source array to initialize the resulting array with.</param>
         <param name="selector">The function to apply to each element from the source array.</param>
         <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array that contains the specified items.</returns>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -728,14 +728,14 @@ This overload allows helper methods or custom builder classes to efficiently avo
         <Parameter Name="selector" Type="System.Func&lt;TSource,TResult&gt;" />
       </Parameters>
       <Docs>
-        <typeparam name="TSource">To be added.</typeparam>
-        <typeparam name="TResult">To be added.</typeparam>
+        <typeparam name="TSource">The type of element stored in the source array.</typeparam>
+        <typeparam name="TResult">The type of element to store in the target array.</typeparam>
         <param name="items">The source array to initialize the resulting array with.</param>
         <param name="start">The index of the first element in the source array to include in the resulting array.</param>
         <param name="length">The number of elements from the source array to include in the resulting array.</param>
         <param name="selector">The function to apply to each element from the source array included in the resulting array.</param>
         <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array that contains the specified items.</returns>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -779,14 +779,14 @@ This overload allows helper methods or custom builder classes to efficiently avo
         <Parameter Name="arg" Type="TArg" />
       </Parameters>
       <Docs>
-        <typeparam name="TSource">To be added.</typeparam>
-        <typeparam name="TArg">To be added.</typeparam>
-        <typeparam name="TResult">To be added.</typeparam>
+        <typeparam name="TSource">The type of element stored in the source array.</typeparam>
+        <typeparam name="TArg">The type of argument to pass to the selector mapping function.</typeparam>
+        <typeparam name="TResult">The type of element to store in the target array.</typeparam>
         <param name="items">The source array to initialize the resulting array with.</param>
         <param name="selector">The function to apply to each element from the source array.</param>
         <param name="arg">An argument to be passed to the selector mapping function.</param>
         <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array that contains the specified items.</returns>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -832,16 +832,16 @@ This overload allows helper methods or custom builder classes to efficiently avo
         <Parameter Name="arg" Type="TArg" />
       </Parameters>
       <Docs>
-        <typeparam name="TSource">To be added.</typeparam>
-        <typeparam name="TArg">To be added.</typeparam>
-        <typeparam name="TResult">To be added.</typeparam>
+        <typeparam name="TSource">The type of element stored in the source array.</typeparam>
+        <typeparam name="TArg">The type of argument to be passed to the selector mapping function.</typeparam>
+        <typeparam name="TResult">The type of element to be stored in the target array.</typeparam>
         <param name="items">The source array to initialize the resulting array with.</param>
         <param name="start">The index of the first element in the source array to include in the resulting array.</param>
         <param name="length">The number of elements from the source array to include in the resulting array.</param>
         <param name="selector">The function to apply to each element from the source array included in the resulting array.</param>
         <param name="arg">An argument to be passed to the selector mapping function.</param>
         <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array that contains the specified items.</returns>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
diff --git a/xml/System.Collections.Immutable/ImmutableArray`1+Builder.xml b/xml/System.Collections.Immutable/ImmutableArray`1+Builder.xml
index cf2aa81ee15..71ddfc0270e 100644
--- a/xml/System.Collections.Immutable/ImmutableArray`1+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableArray`1+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableArray&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableArray&lt;T&gt;+Builder">
+<Type Name="ImmutableArray&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableArray&lt;T&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableArray&lt;T&gt;.Builder : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IList&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.IReadOnlyList&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableArray`1/Builder&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IList`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyList`1&lt;!T&gt;, class System.Collections.IEnumerable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableArray`1.Builder" />
@@ -1029,7 +1029,7 @@
       <Parameters />
       <Docs>
         <summary>Extracts the internal array as an <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> and replaces it              with a zero length array.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array containing the elements of the builder.</returns>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidOperationException">When <see cref="P:System.Collections.Immutable.ImmutableArray`1.Builder.Count" /> doesn't              equal <see cref="P:System.Collections.Immutable.ImmutableArray`1.Builder.Capacity" />.</exception>
       </Docs>
diff --git a/xml/System.Collections.Immutable/ImmutableArray`1.xml b/xml/System.Collections.Immutable/ImmutableArray`1.xml
index 7e2ee3f214d..b80fc6645f0 100644
--- a/xml/System.Collections.Immutable/ImmutableArray`1.xml
+++ b/xml/System.Collections.Immutable/ImmutableArray`1.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableArray&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableArray&lt;T&gt;">
+<Type Name="ImmutableArray&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableArray&lt;T&gt;">
   <TypeSignature Language="C#" Value="public struct ImmutableArray&lt;T&gt; : IEquatable&lt;System.Collections.Immutable.ImmutableArray&lt;T&gt;&gt;, System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IList&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.IReadOnlyList&lt;T&gt;, System.Collections.IList, System.Collections.Immutable.IImmutableList&lt;T&gt;, System.Collections.IStructuralComparable, System.Collections.IStructuralEquatable" />
   <TypeSignature Language="ILAsm" Value=".class public sequential ansi sealed beforefieldinit ImmutableArray`1&lt;T&gt; extends System.ValueType implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IList`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyList`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable, class System.Collections.IList, class System.Collections.Immutable.IImmutableList`1&lt;!T&gt;, class System.Collections.IStructuralComparable, class System.Collections.IStructuralEquatable, class System.IEquatable`1&lt;valuetype System.Collections.Immutable.ImmutableArray`1&lt;!T&gt;&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableArray`1" />
@@ -325,9 +325,9 @@
       </TypeParameters>
       <Parameters />
       <Docs>
-        <typeparam name="TOther">To be added.</typeparam>
+        <typeparam name="TOther">The type of array element to return.</typeparam>
         <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct by casting the underlying array to an array of type <typeparamref name="TOther" />.</summary>
-        <returns>To be added.</returns>
+        <returns>An immutable array instance with elements cast to the new type.</returns>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidCastException">Thrown if the cast is illegal.</exception>
       </Docs>
@@ -366,10 +366,10 @@
         <Parameter Name="items" Type="System.Collections.Immutable.ImmutableArray&lt;TDerived&gt;" />
       </Parameters>
       <Docs>
-        <typeparam name="TDerived">To be added.</typeparam>
+        <typeparam name="TDerived">The type of array element to return.</typeparam>
         <param name="items">The array to initialize the array with. No copy is made.</param>
-        <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct based on the contents             of an existing instance, allowing a covariant static cast to efficiently reuse the existing array.</summary>
-        <returns>To be added.</returns>
+        <summary>Initializes a new instance of the <see cref="T:System.Collections.Immutable.ImmutableArray`1" /> struct based on the contents of an existing instance, allowing a covariant static cast to efficiently reuse the existing array.</summary>
+        <returns>An immutable array instance with elements cast to the new type.</returns>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -2152,8 +2152,8 @@
         <ReturnType>System.Int32</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets the number of array in the collection.</summary>
-        <value>To be added.</value>
+        <summary>Gets the number of items in the collection.</summary>
+        <value>Number of items in the collection.</value>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidOperationException">Thrown if the <see cref="P:System.Collections.Immutable.ImmutableArray`1.IsDefault" /> property returns true.</exception>
       </Docs>
@@ -2421,8 +2421,8 @@
         <ReturnType>System.Int32</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets the number of array in the collection.</summary>
-        <value>To be added.</value>
+        <summary>Gets the number of items in the collection.</summary>
+        <value>The number of items in the collection.</value>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidOperationException">Thrown if the <see cref="P:System.Collections.Immutable.ImmutableArray`1.IsDefault" /> property returns true.</exception>
       </Docs>
@@ -2540,7 +2540,7 @@
       </ReturnValue>
       <Docs>
         <summary>Gets the size of the array.</summary>
-        <value>To be added.</value>
+        <value>The number of items in the collection.</value>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidOperationException">Thrown if the <see cref="P:System.Collections.Immutable.ImmutableArray`1.IsDefault" /> property returns true.</exception>
       </Docs>
@@ -2576,9 +2576,17 @@
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>See the <see cref="T:System.Collections.ICollection" /> interface. Always returns <see langword="true" /> since since immutable collections are thread-safe.</summary>
+        <value>Boolean value determining whether the collection is thread-safe.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableArray`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -2613,7 +2621,7 @@
       </ReturnValue>
       <Docs>
         <summary>Gets the sync root.</summary>
-        <value>To be added.</value>
+        <value>An object for synchronizing access to the collection.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
diff --git a/xml/System.Collections.Immutable/ImmutableDictionary`2+Builder.xml b/xml/System.Collections.Immutable/ImmutableDictionary`2+Builder.xml
index 6531a541b9a..e428dce1b1c 100644
--- a/xml/System.Collections.Immutable/ImmutableDictionary`2+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableDictionary`2+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;+Builder" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;+Builder">
+<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;+Builder" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableDictionary&lt;TKey,TValue&gt;.Builder : System.Collections.Generic.ICollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IDictionary&lt;TKey,TValue&gt;, System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyCollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyDictionary&lt;TKey,TValue&gt;, System.Collections.IDictionary" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableDictionary`2/Builder&lt;TKey, TValue&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.Generic.IEnumerable`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.ICollection, class System.Collections.IDictionary, class System.Collections.IEnumerable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableDictionary`2.Builder" />
@@ -693,9 +693,9 @@
         <Parameter Name="arrayIndex" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="array">To be added.</param>
-        <param name="arrayIndex">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="array">The one-dimensional array that is the destination of the elements copied from the dictionary. The array must have zero-based indexing.</param>
+        <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
+        <summary>Copies the elements of the dictionary to an array of type <see cref="T:System.Collections.Generic.KeyValuePair`2" />, starting at the specified array index.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -902,7 +902,15 @@
         <summary>Gets a value that indicates whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -938,7 +946,15 @@
       <Docs>
         <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
         <value>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Add">
@@ -1096,7 +1112,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.IDictionary" /> object has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IDictionary" /> object has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.IsReadOnly">
@@ -1128,7 +1152,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Item">
@@ -1162,7 +1194,7 @@
       <Docs>
         <param name="key">The key.</param>
         <summary>Gets or sets the element with the specified key.</summary>
-        <value>To be added.</value>
+        <value>Value stored under specified key.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1194,7 +1226,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Remove">
diff --git a/xml/System.Collections.Immutable/ImmutableDictionary`2+Enumerator.xml b/xml/System.Collections.Immutable/ImmutableDictionary`2+Enumerator.xml
index 2c5ef7e9a18..4a89217e68c 100644
--- a/xml/System.Collections.Immutable/ImmutableDictionary`2+Enumerator.xml
+++ b/xml/System.Collections.Immutable/ImmutableDictionary`2+Enumerator.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;+Enumerator">
+<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;+Enumerator">
   <TypeSignature Language="C#" Value="public struct ImmutableDictionary&lt;TKey,TValue&gt;.Enumerator : System.Collections.Generic.IEnumerator&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public sequential ansi sealed beforefieldinit ImmutableDictionary`2/Enumerator&lt;TKey, TValue&gt; extends System.ValueType implements class System.Collections.Generic.IEnumerator`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.IEnumerator, class System.IDisposable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableDictionary`2.Enumerator" />
@@ -197,8 +197,16 @@
       </ReturnValue>
       <Docs>
         <summary>Gets the current element.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <value>Current element in enumeration.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2.Enumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
   </Members>
diff --git a/xml/System.Collections.Immutable/ImmutableDictionary`2.xml b/xml/System.Collections.Immutable/ImmutableDictionary`2.xml
index 38452ced7cf..aa3c88c7c6f 100644
--- a/xml/System.Collections.Immutable/ImmutableDictionary`2.xml
+++ b/xml/System.Collections.Immutable/ImmutableDictionary`2.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;">
+<Type Name="ImmutableDictionary&lt;TKey,TValue&gt;" FullName="System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;">
   <TypeSignature Language="C#" Value="public sealed class ImmutableDictionary&lt;TKey,TValue&gt; : System.Collections.Generic.ICollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IDictionary&lt;TKey,TValue&gt;, System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyCollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyDictionary&lt;TKey,TValue&gt;, System.Collections.IDictionary, System.Collections.Immutable.IImmutableDictionary&lt;TKey,TValue&gt;" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit ImmutableDictionary`2&lt;TKey, TValue&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.Generic.IEnumerable`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.ICollection, class System.Collections.IDictionary, class System.Collections.IEnumerable, class System.Collections.Immutable.IImmutableDictionary`2&lt;!TKey, !TValue&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableDictionary`2" />
@@ -681,8 +681,8 @@
         <Parameter Name="item" Type="System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="item">The object to add to the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
+        <summary>Adds an item to the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -713,7 +713,7 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
+        <summary>Removes all items from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -747,9 +747,9 @@
         <Parameter Name="arrayIndex" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="array">To be added.</param>
-        <param name="arrayIndex">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.ICollection`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
+        <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
+        <summary>Copies the elements of the <see cref="T:System.Collections.Generic.ICollection`1" /> to an <see cref="T:System.Array" />, starting at a particular <see cref="T:System.Array" /> index.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -779,8 +779,9 @@
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
+        <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
+        <value>
+          <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -813,9 +814,10 @@
         <Parameter Name="item" Type="System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="item">The object to remove from the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
+        <summary>Removes the first occurrence of a specific object from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
+        <returns>
+          <see langword="true" /> if <paramref name="item" /> was successfully removed from the <see cref="T:System.Collections.Generic.ICollection`1" />; otherwise, <see langword="false" />. This method also returns <see langword="false" /> if <paramref name="item" /> is not found in the original <see cref="T:System.Collections.Generic.ICollection`1" />.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1097,7 +1099,15 @@
         <summary>Gets a value indicating whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1329,7 +1339,15 @@
         <summary>Gets a value indicating whether the <see cref="T:System.Collections.IDictionary" /> object has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IDictionary" /> object has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.IsReadOnly">
@@ -1361,7 +1379,15 @@
         <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Item">
@@ -1395,7 +1421,7 @@
       <Docs>
         <param name="key">The key.</param>
         <summary>Gets or sets the element with the specified key.</summary>
-        <value>To be added.</value>
+        <value>The value stored under the specified key.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1427,7 +1453,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Remove">
@@ -1499,7 +1533,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -1571,10 +1613,10 @@
         <Parameter Name="value" Type="TValue" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="key">Key of the entry to be added.</param>
+        <param name="value">Value of the entry to be added.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface</summary>
+        <returns>A new immutable dictionary that contains the additional key/value pair.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1607,9 +1649,9 @@
         <Parameter Name="pairs" Type="System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;" />
       </Parameters>
       <Docs>
-        <param name="pairs">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="pairs">Sequence of key/value pairs to be added to the dictionary.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface</summary>
+        <returns>A new immutable dictionary that contains the additional key/value pairs.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1674,9 +1716,9 @@
         <Parameter Name="key" Type="TKey" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="key">Key of the entry to be removed.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface</summary>
+        <returns>A new immutable dictionary with the specified element removed; or this instance if the specified key cannot be found in the dictionary.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1709,9 +1751,9 @@
         <Parameter Name="keys" Type="System.Collections.Generic.IEnumerable&lt;TKey&gt;" />
       </Parameters>
       <Docs>
-        <param name="keys">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="keys">Sequence of keys to be removed.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface</summary>
+        <returns>A new immutable dictionary with the specified keys removed; or this instance if the specified keys cannot be found in the dictionary.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1745,10 +1787,10 @@
         <Parameter Name="value" Type="TValue" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="key">Key of entry to be added.</param>
+        <param name="value">Value of the entry to be added.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface</summary>
+        <returns>A new immutable dictionary that contains the specified key/value pair.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
diff --git a/xml/System.Collections.Immutable/ImmutableHashSet`1+Builder.xml b/xml/System.Collections.Immutable/ImmutableHashSet`1+Builder.xml
index ab2ca32f36d..4600c47fb6d 100644
--- a/xml/System.Collections.Immutable/ImmutableHashSet`1+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableHashSet`1+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableHashSet&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;+Builder">
+<Type Name="ImmutableHashSet&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableHashSet&lt;T&gt;.Builder : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.ISet&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableHashSet`1/Builder&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.ISet`1&lt;!T&gt;, class System.Collections.IEnumerable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableHashSet`1.Builder" />
diff --git a/xml/System.Collections.Immutable/ImmutableHashSet`1+Enumerator.xml b/xml/System.Collections.Immutable/ImmutableHashSet`1+Enumerator.xml
index 31bfa07b80a..edf0fa570eb 100644
--- a/xml/System.Collections.Immutable/ImmutableHashSet`1+Enumerator.xml
+++ b/xml/System.Collections.Immutable/ImmutableHashSet`1+Enumerator.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableHashSet&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;+Enumerator">
+<Type Name="ImmutableHashSet&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;+Enumerator">
   <TypeSignature Language="C#" Value="public struct ImmutableHashSet&lt;T&gt;.Enumerator : System.Collections.Generic.IEnumerator&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public sequential ansi sealed beforefieldinit ImmutableHashSet`1/Enumerator&lt;T&gt; extends System.ValueType implements class System.Collections.Generic.IEnumerator`1&lt;!T&gt;, class System.Collections.IEnumerator, class System.IDisposable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableHashSet`1.Enumerator" />
@@ -197,7 +197,15 @@
       <Docs>
         <summary>Gets the current element.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableHashSet`1.Enumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
   </Members>
diff --git a/xml/System.Collections.Immutable/ImmutableHashSet`1.xml b/xml/System.Collections.Immutable/ImmutableHashSet`1.xml
index 52d22460c35..3194cc1e6db 100644
--- a/xml/System.Collections.Immutable/ImmutableHashSet`1.xml
+++ b/xml/System.Collections.Immutable/ImmutableHashSet`1.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableHashSet&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;">
+<Type Name="ImmutableHashSet&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableHashSet&lt;T&gt;">
   <TypeSignature Language="C#" Value="public sealed class ImmutableHashSet&lt;T&gt; : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.ISet&lt;T&gt;, System.Collections.ICollection, System.Collections.Immutable.IImmutableSet&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit ImmutableHashSet`1&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.ISet`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable, class System.Collections.Immutable.IImmutableSet`1&lt;!T&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableHashSet`1" />
@@ -1194,7 +1194,15 @@
       <Docs>
         <summary>See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableHashSet`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1230,7 +1238,15 @@
       <Docs>
         <summary>See <see cref="T:System.Collections.ICollection" />.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableHashSet`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
diff --git a/xml/System.Collections.Immutable/ImmutableInterlocked.xml b/xml/System.Collections.Immutable/ImmutableInterlocked.xml
index 530432cf8e3..497425c6876 100644
--- a/xml/System.Collections.Immutable/ImmutableInterlocked.xml
+++ b/xml/System.Collections.Immutable/ImmutableInterlocked.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableInterlocked" FullName="System.Collections.Immutable.ImmutableInterlocked">
+<Type Name="ImmutableInterlocked" FullName="System.Collections.Immutable.ImmutableInterlocked">
   <TypeSignature Language="C#" Value="public static class ImmutableInterlocked" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi abstract sealed beforefieldinit ImmutableInterlocked extends System.Object" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableInterlocked" />
@@ -669,11 +669,13 @@
         <Parameter Name="transformer" Type="System.Func&lt;System.Collections.Immutable.ImmutableArray&lt;T&gt;,System.Collections.Immutable.ImmutableArray&lt;T&gt;&gt;" Index="1" FrameworkAlternate="net-5.0" />
       </Parameters>
       <Docs>
-        <typeparam name="T">To be added.</typeparam>
-        <param name="location">To be added.</param>
-        <param name="transformer">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <typeparam name="T">The type of data in the immutable array.</typeparam>
+        <param name="location">The immutable array to be changed.</param>
+        <param name="transformer">A function that produces the new array from the old. This function should be side-effect free, as it may run multiple times when races occur with other threads.</param>
+        <summary>Mutates an immutable array in-place with optimistic locking transaction semantics via a specified transformation function.
+ The transformation is retried as many times as necessary to win the optimistic locking race.</summary>
+        <returns>
+          <see langword="true" /> if the location's value is changed by applying the result of the <paramref name="transformer" /> function; <see langword="false" /> if the location's value remained the same because the last invocation of <paramref name="transformer" /> returned the existing value.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -745,13 +747,15 @@
         <Parameter Name="transformerArgument" Type="TArg" Index="2" FrameworkAlternate="net-5.0" />
       </Parameters>
       <Docs>
-        <typeparam name="T">To be added.</typeparam>
-        <typeparam name="TArg">To be added.</typeparam>
-        <param name="location">To be added.</param>
-        <param name="transformer">To be added.</param>
-        <param name="transformerArgument">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <typeparam name="T">The type of data in the immutable array.</typeparam>
+        <typeparam name="TArg">The type of argument passed to the <paramref name="transformer" />.</typeparam>
+        <param name="location">The immutable array to be changed.</param>
+        <param name="transformer">A function that produces the new array from the old. This function should be side-effect free, as it may run multiple times when races occur with other threads.</param>
+        <param name="transformerArgument">The argument to pass to <paramref name="transformer" />.</param>
+        <summary>Mutates an immutable array in-place with optimistic locking transaction semantics via a specified transformation function.
+ The transformation is retried as many times as necessary to win the optimistic locking race.</summary>
+        <returns>
+          <see langword="true" /> if the location's value is changed by applying the result of the <paramref name="transformer" /> function; <see langword="false" /> if the location's value remained the same because the last invocation of <paramref name="transformer" /> returned the existing value.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
diff --git a/xml/System.Collections.Immutable/ImmutableList`1+Builder.xml b/xml/System.Collections.Immutable/ImmutableList`1+Builder.xml
index 5ef3a0c6773..774bd73eaf6 100644
--- a/xml/System.Collections.Immutable/ImmutableList`1+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableList`1+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableList&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;+Builder">
+<Type Name="ImmutableList&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableList&lt;T&gt;.Builder : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IList&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.IReadOnlyList&lt;T&gt;, System.Collections.IList" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableList`1/Builder&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IList`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyList`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable, class System.Collections.IList" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableList`1.Builder" />
@@ -1855,7 +1855,15 @@
         <summary>Gets a value that indicates whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1891,7 +1899,15 @@
       <Docs>
         <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
         <value>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -2175,7 +2191,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.IList" /> has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IList" /> has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1.Builder> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.IsReadOnly">
@@ -2207,7 +2231,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1.Builder> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Item">
diff --git a/xml/System.Collections.Immutable/ImmutableList`1+Enumerator.xml b/xml/System.Collections.Immutable/ImmutableList`1+Enumerator.xml
index 13c7d380f2a..07e9fcbdb7b 100644
--- a/xml/System.Collections.Immutable/ImmutableList`1+Enumerator.xml
+++ b/xml/System.Collections.Immutable/ImmutableList`1+Enumerator.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableList&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;+Enumerator">
+<Type Name="ImmutableList&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;+Enumerator">
   <TypeSignature Language="C#" Value="public struct ImmutableList&lt;T&gt;.Enumerator : System.Collections.Generic.IEnumerator&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public sequential ansi sealed beforefieldinit ImmutableList`1/Enumerator&lt;T&gt; extends System.ValueType implements class System.Collections.Generic.IEnumerator`1&lt;!T&gt;, class System.Collections.IEnumerator, class System.IDisposable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableList`1.Enumerator" />
@@ -210,7 +210,15 @@
       <Docs>
         <summary>The current element.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1.Enumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
   </Members>
diff --git a/xml/System.Collections.Immutable/ImmutableList`1.xml b/xml/System.Collections.Immutable/ImmutableList`1.xml
index 29ad3045fb8..dd3f4c1ad54 100644
--- a/xml/System.Collections.Immutable/ImmutableList`1.xml
+++ b/xml/System.Collections.Immutable/ImmutableList`1.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableList&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;">
+<Type Name="ImmutableList&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableList&lt;T&gt;">
   <TypeSignature Language="C#" Value="public sealed class ImmutableList&lt;T&gt; : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IList&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.IReadOnlyList&lt;T&gt;, System.Collections.IList, System.Collections.Immutable.IImmutableList&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit ImmutableList`1&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IList`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyList`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable, class System.Collections.IList, class System.Collections.Immutable.IImmutableList`1&lt;!T&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableList`1" />
@@ -2097,9 +2097,9 @@
         <Parameter Name="index" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
+        <param name="index">The zero-based index of the item to access.</param>
         <summary>Gets or sets the value at the specified index.</summary>
-        <value>To be added.</value>
+        <value>Value stored in the specified index.</value>
         <remarks>To be added.</remarks>
         <exception cref="T:System.IndexOutOfRangeException">Thrown from getter when <paramref name="index" /> is negative or not less than <see cref="P:System.Collections.Immutable.ImmutableList`1.Count" />.</exception>
         <exception cref="T:System.NotSupportedException">Always thrown from the setter.</exception>
@@ -2221,9 +2221,17 @@
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>This type is immutable, so it is always thread-safe. See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
+        <value>Boolean value determining whether the collection is thread-safe.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -2258,8 +2266,16 @@
       </ReturnValue>
       <Docs>
         <summary>See <see cref="T:System.Collections.ICollection" />.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <value>Object used for synchronizing access to the collection.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -2543,7 +2559,15 @@
         <summary>Gets a value indicating whether the <see cref="T:System.Collections.IList" /> has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IList" /> has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.IsReadOnly">
@@ -2575,7 +2599,15 @@
         <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableList`1> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Item">
diff --git a/xml/System.Collections.Immutable/ImmutableQueue`1.xml b/xml/System.Collections.Immutable/ImmutableQueue`1.xml
index 92edf1b2f05..60ec8409746 100644
--- a/xml/System.Collections.Immutable/ImmutableQueue`1.xml
+++ b/xml/System.Collections.Immutable/ImmutableQueue`1.xml
@@ -325,7 +325,7 @@
       <Parameters />
       <Docs>
         <summary>Gets a read-only reference to the element at the front of the queue.</summary>
-        <returns>To be added.</returns>
+        <returns>Read-only reference to the element at the front of the queue.</returns>
         <remarks>To be added.</remarks>
         <exception cref="T:System.InvalidOperationException">The queue is empty.</exception>
       </Docs>
diff --git a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Builder.xml b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Builder.xml
index 6839f18a622..fc4c2ca0c2e 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;+Builder" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;+Builder">
+<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;+Builder" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableSortedDictionary&lt;TKey,TValue&gt;.Builder : System.Collections.Generic.ICollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IDictionary&lt;TKey,TValue&gt;, System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyCollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyDictionary&lt;TKey,TValue&gt;, System.Collections.IDictionary" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableSortedDictionary`2/Builder&lt;TKey, TValue&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.Generic.IEnumerable`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.ICollection, class System.Collections.IDictionary, class System.Collections.IEnumerable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder" />
@@ -669,9 +669,9 @@
         <Parameter Name="arrayIndex" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="array">To be added.</param>
-        <param name="arrayIndex">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="array">The one-dimensional array that is the destination of the elements copied from the dictionary. The array must have zero-based indexing.</param>
+        <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
+        <summary>See <see cref="T:System.Collections.Generic.IDictionary`2" /></summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -732,8 +732,8 @@
         <ReturnType>System.Collections.Generic.ICollection&lt;TKey&gt;</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
+        <summary>Returns a collection containing all keys stored in the dictionary. See <see cref="T:System.Collections.Generic.IDictionary`2" /></summary>
+        <value>A collection containing all keys stored in the dictionary.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -763,8 +763,8 @@
         <ReturnType>System.Collections.Generic.ICollection&lt;TValue&gt;</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
+        <summary>Returns a collection containing all values stored in the dictionary. See <see cref="T:System.Collections.Generic.IDictionary`2" /></summary>
+        <value>A collection containing all values stored in the dictionary.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -795,8 +795,8 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <summary>See <see cref="T:System.Collections.Generic.IDictionary`2" /></summary>
+        <returns>An enumerator that can be used to iterate through the collection.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -879,7 +879,15 @@
         <summary>Gets a value that indicates whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -915,7 +923,15 @@
       <Docs>
         <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
         <value>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Add">
@@ -1072,7 +1088,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.IDictionary" /> object has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IDictionary" /> object has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.IsReadOnly">
@@ -1104,7 +1128,15 @@
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Item">
@@ -1138,7 +1170,7 @@
       <Docs>
         <param name="key">The key.</param>
         <summary>Gets or sets the element with the specified key.</summary>
-        <value>To be added.</value>
+        <value>The value associated with the specified key.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1170,7 +1202,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Remove">
@@ -1242,7 +1282,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Builder> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -1462,9 +1510,9 @@
         <Parameter Name="key" Type="TKey" Index="0" FrameworkAlternate="netcore-2.1;netcore-2.2;netcore-3.0;netcore-3.1;net-5.0" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
+        <param name="key">Key of the entry to be looked up.</param>
         <summary>Returns a read-only reference to the value associated with the provided <paramref name="key" />.</summary>
-        <returns>To be added.</returns>
+        <returns>A read-only reference to the value associated with the provided <paramref name="key" />.</returns>
         <remarks>To be added.</remarks>
         <exception cref="T:System.Collections.Generic.KeyNotFoundException">The <paramref name="key" /> is not present.</exception>
       </Docs>
diff --git a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Enumerator.xml b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Enumerator.xml
index d40a560f099..3cb47280a05 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Enumerator.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2+Enumerator.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;+Enumerator">
+<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;+Enumerator">
   <TypeSignature Language="C#" Value="public struct ImmutableSortedDictionary&lt;TKey,TValue&gt;.Enumerator : System.Collections.Generic.IEnumerator&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public sequential ansi sealed beforefieldinit ImmutableSortedDictionary`2/Enumerator&lt;TKey, TValue&gt; extends System.ValueType implements class System.Collections.Generic.IEnumerator`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.IEnumerator, class System.IDisposable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedDictionary`2.Enumerator" />
@@ -211,7 +211,15 @@
       <Docs>
         <summary>The current element.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2.Enumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
   </Members>
diff --git a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2.xml b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2.xml
index 6d9628081b4..442f0d0061a 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedDictionary`2.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedDictionary`2.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;">
+<Type Name="ImmutableSortedDictionary&lt;TKey,TValue&gt;" FullName="System.Collections.Immutable.ImmutableSortedDictionary&lt;TKey,TValue&gt;">
   <TypeSignature Language="C#" Value="public sealed class ImmutableSortedDictionary&lt;TKey,TValue&gt; : System.Collections.Generic.ICollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IDictionary&lt;TKey,TValue&gt;, System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyCollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;, System.Collections.Generic.IReadOnlyDictionary&lt;TKey,TValue&gt;, System.Collections.IDictionary, System.Collections.Immutable.IImmutableDictionary&lt;TKey,TValue&gt;" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit ImmutableSortedDictionary`2&lt;TKey, TValue&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.Generic.IEnumerable`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;valuetype System.Collections.Generic.KeyValuePair`2&lt;!TKey, !TValue&gt;&gt;, class System.Collections.Generic.IReadOnlyDictionary`2&lt;!TKey, !TValue&gt;, class System.Collections.ICollection, class System.Collections.IDictionary, class System.Collections.IEnumerable, class System.Collections.Immutable.IImmutableDictionary`2&lt;!TKey, !TValue&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedDictionary`2" />
@@ -663,8 +663,8 @@
         <Parameter Name="item" Type="System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="item">The object to add to the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
+        <summary>Adds an item to the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -695,7 +695,7 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
+        <summary>Removes all items from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -729,9 +729,9 @@
         <Parameter Name="arrayIndex" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="array">To be added.</param>
-        <param name="arrayIndex">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.ICollection`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
+        <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
+        <summary>Copies the elements of the <see cref="T:System.Collections.Generic.ICollection`1" /> to an <see cref="T:System.Array" />, starting at a particular <see cref="T:System.Array" /> index.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -761,8 +761,9 @@
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
+        <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
+        <value>
+          <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -795,9 +796,10 @@
         <Parameter Name="item" Type="System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="item">The object to remove from the <see cref="T:System.Collections.Generic.ICollection`1" />.</param>
+        <summary>Removes the first occurrence of a specific object from the <see cref="T:System.Collections.Generic.ICollection`1" />.</summary>
+        <returns>
+          <see langword="true" /> if <paramref name="item" /> was successfully removed from the <see cref="T:System.Collections.Generic.ICollection`1" />; otherwise, <see langword="false" />. This method also returns <see langword="false" /> if <paramref name="item" /> is not found in the original <see cref="T:System.Collections.Generic.ICollection`1" />.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -866,7 +868,7 @@
         <Parameter Name="key" Type="TKey" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
+        <param name="key">The object to use as the key of the element to access.</param>
         <summary>Gets or sets the <typeparamref name="TValue" /> with the specified key.</summary>
         <value>An object of type <typeparamref name="TValue" /> associated with the <paramref name="key" />.</value>
         <remarks>To be added.</remarks>
@@ -1079,7 +1081,15 @@
         <summary>Gets a value indicating whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread-safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1115,7 +1125,15 @@
       <Docs>
         <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
         <value>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Add">
@@ -1311,7 +1329,15 @@
         <summary>Gets a value indicating whether the <see cref="T:System.Collections.IDictionary" /> object has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IDictionary" /> object has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.IsReadOnly">
@@ -1375,9 +1401,9 @@
         <Parameter Name="key" Type="System.Object" />
       </Parameters>
       <Docs>
-        <param name="key">The key.</param>
+        <param name="key">The key of the element to be accessed.</param>
         <summary>Gets or sets the element with the specified key.</summary>
-        <value>To be added.</value>
+        <value>Value stored under the specified key.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1409,7 +1435,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the keys of the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IDictionary.Remove">
@@ -1481,7 +1515,15 @@
       <Docs>
         <summary>Gets an <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the <see cref="T:System.Collections.Generic.IDictionary`2" />.</summary>
         <value>An <see cref="T:System.Collections.Generic.ICollection`1" /> containing the values in the object that implements <see cref="T:System.Collections.Generic.IDictionary`2" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedDictionary`2> instance is cast to an <xref:System.Collections.IDictionary> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -1553,9 +1595,9 @@
         <Parameter Name="value" Type="TValue" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="key">Key of the entry to be added.</param>
+        <param name="value">Value of the entry to be added.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1589,8 +1631,8 @@
         <Parameter Name="pairs" Type="System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;" />
       </Parameters>
       <Docs>
-        <param name="pairs">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="pairs">Sequence of key/value pairs to be added.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1622,7 +1664,7 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1656,8 +1698,8 @@
         <Parameter Name="key" Type="TKey" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="key">Key of entry to be removed.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1691,8 +1733,8 @@
         <Parameter Name="keys" Type="System.Collections.Generic.IEnumerable&lt;TKey&gt;" />
       </Parameters>
       <Docs>
-        <param name="keys">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="keys">Sequence of keys to be removed.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1727,9 +1769,9 @@
         <Parameter Name="value" Type="TValue" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="key">Key of entry to be updated.</param>
+        <param name="value">Value of entry to be updated.</param>
+        <summary>See the <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> interface.</summary>
         <returns>The <see cref="T:System.Collections.Immutable.IImmutableDictionary`2" /> instance.</returns>
         <remarks>To be added.</remarks>
       </Docs>
@@ -1950,9 +1992,9 @@
         <Parameter Name="key" Type="TKey" Index="0" FrameworkAlternate="netcore-2.1;netcore-2.2;netcore-3.0;netcore-3.1;net-5.0" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
+        <param name="key">Key of the entry to be looked up.</param>
         <summary>Returns a read-only reference to the value associated with the provided <paramref name="key" />.</summary>
-        <returns>To be added.</returns>
+        <returns>A read-only reference to the value associated with the provided <paramref name="key" />.</returns>
         <remarks>To be added.</remarks>
         <exception cref="T:System.Collections.Generic.KeyNotFoundException">The <paramref name="key" /> is not present.</exception>
       </Docs>
diff --git a/xml/System.Collections.Immutable/ImmutableSortedSet`1+Builder.xml b/xml/System.Collections.Immutable/ImmutableSortedSet`1+Builder.xml
index b4aaf3d5ec5..232647133b3 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedSet`1+Builder.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedSet`1+Builder.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedSet&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;+Builder">
+<Type Name="ImmutableSortedSet&lt;T&gt;+Builder" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;+Builder">
   <TypeSignature Language="C#" Value="public sealed class ImmutableSortedSet&lt;T&gt;.Builder : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.ISet&lt;T&gt;, System.Collections.ICollection" />
   <TypeSignature Language="ILAsm" Value=".class nested public auto ansi sealed beforefieldinit ImmutableSortedSet`1/Builder&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.ISet`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedSet`1.Builder" />
@@ -1007,7 +1007,15 @@
         <summary>Gets a value that indicates whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread-safe).</summary>
         <value>
           <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread-safe); otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1043,7 +1051,15 @@
       <Docs>
         <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
         <value>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1.Builder> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
diff --git a/xml/System.Collections.Immutable/ImmutableSortedSet`1+Enumerator.xml b/xml/System.Collections.Immutable/ImmutableSortedSet`1+Enumerator.xml
index 6e69fe68e2a..273e92d43fb 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedSet`1+Enumerator.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedSet`1+Enumerator.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedSet&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;+Enumerator">
+<Type Name="ImmutableSortedSet&lt;T&gt;+Enumerator" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;+Enumerator">
   <TypeSignature Language="C#" Value="public struct ImmutableSortedSet&lt;T&gt;.Enumerator : System.Collections.Generic.IEnumerator&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class nested public sequential ansi sealed beforefieldinit ImmutableSortedSet`1/Enumerator&lt;T&gt; extends System.ValueType implements class System.Collections.Generic.IEnumerator`1&lt;!T&gt;, class System.Collections.IEnumerator, class System.IDisposable" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedSet`1.Enumerator" />
@@ -218,7 +218,15 @@
       <Docs>
         <summary>The current element.</summary>
         <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1.Enumerator> instance is cast to an <xref:System.Collections.IEnumerator> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
   </Members>
diff --git a/xml/System.Collections.Immutable/ImmutableSortedSet`1.xml b/xml/System.Collections.Immutable/ImmutableSortedSet`1.xml
index 0a275efe74f..1bce16d18e0 100644
--- a/xml/System.Collections.Immutable/ImmutableSortedSet`1.xml
+++ b/xml/System.Collections.Immutable/ImmutableSortedSet`1.xml
@@ -1,4 +1,4 @@
-<Type Name="ImmutableSortedSet&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;">
+<Type Name="ImmutableSortedSet&lt;T&gt;" FullName="System.Collections.Immutable.ImmutableSortedSet&lt;T&gt;">
   <TypeSignature Language="C#" Value="public sealed class ImmutableSortedSet&lt;T&gt; : System.Collections.Generic.ICollection&lt;T&gt;, System.Collections.Generic.IEnumerable&lt;T&gt;, System.Collections.Generic.IList&lt;T&gt;, System.Collections.Generic.IReadOnlyCollection&lt;T&gt;, System.Collections.Generic.IReadOnlyList&lt;T&gt;, System.Collections.Generic.ISet&lt;T&gt;, System.Collections.IList, System.Collections.Immutable.IImmutableSet&lt;T&gt;" />
   <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit ImmutableSortedSet`1&lt;T&gt; extends System.Object implements class System.Collections.Generic.ICollection`1&lt;!T&gt;, class System.Collections.Generic.IEnumerable`1&lt;!T&gt;, class System.Collections.Generic.IList`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyCollection`1&lt;!T&gt;, class System.Collections.Generic.IReadOnlyList`1&lt;!T&gt;, class System.Collections.Generic.ISet`1&lt;!T&gt;, class System.Collections.ICollection, class System.Collections.IEnumerable, class System.Collections.IList, class System.Collections.Immutable.IImmutableSet`1&lt;!T&gt;" />
   <TypeSignature Language="DocId" Value="T:System.Collections.Immutable.ImmutableSortedSet`1" />
@@ -1261,8 +1261,8 @@ This member is an explicit interface member implementation. It can be used only
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>See the <see cref="T:System.Collections.Generic.ICollection`1" /> interface.</summary>
-        <value>To be added.</value>
+        <summary>Returns true, since immutable collections are always read-only. See the <see cref="T:System.Collections.Generic.ICollection`1" /> interface.</summary>
+        <value>A boolean value indicating whether the collection is read-only.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1435,9 +1435,9 @@ This member is an explicit interface member implementation. It can be used only
         <Parameter Name="index" Type="System.Int32" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
+        <param name="index">The zero-based index of the item to access.</param>
         <summary>See the <see cref="T:System.Collections.Generic.IList`1" /> interface.</summary>
-        <value>To be added.</value>
+        <value>The element stored at the specified index.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1798,9 +1798,17 @@ This member is an explicit interface member implementation. It can be used only
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Returns true, since immutable collections are always thread-safe. See the <see cref="T:System.Collections.ICollection" /> interface.</summary>
+        <value>A boolean value indicating whether the collection is thread-safe.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.SyncRoot">
@@ -1835,8 +1843,16 @@ This member is an explicit interface member implementation. It can be used only
       </ReturnValue>
       <Docs>
         <summary>See <see cref="T:System.Collections.ICollection" />.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <value>Object used for synchronizing access to the collection.</value>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1> instance is cast to an <xref:System.Collections.ICollection> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IEnumerable.GetEnumerator">
@@ -2148,7 +2164,15 @@ This member is an explicit interface member implementation. It can be used only
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.IList" /> has a fixed size.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.IList" /> has a fixed size; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.IsReadOnly">
@@ -2180,7 +2204,15 @@ This member is an explicit interface member implementation. It can be used only
         <summary>Gets a value that indicates whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
         <value>
           <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />.</value>
-        <remarks>To be added.</remarks>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Collections.Immutable.ImmutableSortedSet`1> instance is cast to an <xref:System.Collections.IList> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Item">