diff --git a/source/index.txt b/source/index.txt
index 55df6e49..85e154ef 100644
--- a/source/index.txt
+++ b/source/index.txt
@@ -25,6 +25,7 @@
    /issues-and-help
    /compatibility
    Validate Driver Artifact Signatures </validate-signatures>
+   /whats-new
    View the Source <https://github.com/mongodb/mongo-java-driver/tree/master/driver-kotlin-sync>
    API Documentation <{+api+}/com.mongodb.kotlin.client/index.html>
 
diff --git a/source/whats-new.txt b/source/whats-new.txt
index 8a5cb77b..a5743dfe 100644
--- a/source/whats-new.txt
+++ b/source/whats-new.txt
@@ -4,4 +4,144 @@
 What's New
 ==========
 
-.. TODO
\ No newline at end of file
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 1
+   :class: singlecol
+
+Learn what's new in:
+
+* :ref:`Version 5.1.3 <kotlin-sync-version-5.1.3>`
+* :ref:`Version 5.1.2 <kotlin-sync-version-5.1.2>`
+* :ref:`Version 5.1.1 <kotlin-sync-version-5.1.1>`
+* :ref:`Version 5.1 <kotlin-sync-version-5.1>`
+* :ref:`Version 5.0 <kotlin-sync-version-5.0>`
+
+.. _kotlin-sync-version-5.1.3:
+
+What's New in 5.1.3
+-------------------
+
+The 5.1.3 driver patch release includes the following changes:
+
+.. sharedinclude:: dbx/jvm/v5.1.3-wn-items.rst
+
+.. _kotlin-sync-version-5.1.2:
+
+What's New in 5.1.2
+-------------------
+
+The 5.1.2 driver patch release includes the following changes:
+
+- Support for encoding Kotlin data classes with nullable
+  generic parameter types. For example, you can encode the ``Container`` class
+  in the following code:
+  
+  .. code-block:: kotlin
+
+     @Serializable
+     data class Box<T>(
+         val boxed: T
+     )
+     
+     @Serializable
+     data class Container(
+         val box: Box<String?>
+     )
+
+.. _kotlin-sync-version-5.1.1:
+
+What's New in 5.1.1
+-------------------
+
+The 5.1.1 driver patch release includes the following changes:
+
+- When using the ``MONGODB-OIDC`` authentication mechanism, you must not
+  include comma characters in the ``authMechanismProperties`` connection
+  string value. 
+  
+.. TODO: Link to OIDC content once completed
+.. ex. To learn more about this behavior, see the
+  :ref:`MONGODB-OIDC <kotlin-sync-oidc>` section of the Enterprise
+  Authentication guide.
+
+.. _kotlin-sync-version-5.1:
+
+What's New in 5.1
+-----------------
+
+.. warning:: Deprecations in this release
+
+   To avoid breaking changes in future major releases of the driver,
+   replace any application code that depends on deprecated program elements.
+
+This section includes the following information:
+
+- :ref:`kotlin-sync-deprecations-5.1`
+- :ref:`kotlin-sync-improvements-5.1`
+- :ref:`kotlin-sync-new-features-5.1`
+
+.. _kotlin-sync-deprecations-5.1:
+
+Deprecations in 5.1
+~~~~~~~~~~~~~~~~~~~
+
+- Support for {+mdb-server+} v3.6 is deprecated and will be removed in the
+  next driver version release. To learn how to upgrade your {+mdb-server+}
+  deployment, see :manual:`Release Notes </release-notes>` in the {+mdb-server+}
+  manual.
+
+.. _kotlin-sync-improvements-5.1:
+
+Improvements in 5.1
+~~~~~~~~~~~~~~~~~~~
+
+- Internal testing of GraalVM native image technology. These tests involve building
+  native applications by using the GraalVM native-image tool.
+
+- Enhanced support for the ``MONGODB-OIDC`` authentication mechanism.
+
+.. TODO: Link to OIDC content once completed
+.. ex. To learn more about OIDC, see the
+  :ref:`MONGODB-OIDC <kotlin-sync-oidc>` section of the Enterprise
+  Authentication guide.
+
+- Fixes an issue in which operations used the incorrect codec when using
+  a polymorphic ``MongoCollection`` instance. This ensures that
+  discriminator information is not lost when using ``bson-kotlinx``.
+
+- Fixes an issue in which the class discriminator was the first field
+  when decoding, resulting in field type errors when using a polymorphic
+  ``MongoCollection`` instance.
+
+.. _kotlin-sync-new-features-5.1:
+
+New Features in 5.1
+~~~~~~~~~~~~~~~~~~~
+
+- Support for polymorphic serialization.
+
+.. TODO: Add link to Kotlin Serialization page when ready: https://jira.mongodb.org/browse/DOCSP-42666 . 
+.. ex. To learn more, see the :ref:`kotlin-sync-polymorphic` section of the Kotlin Sync Serialization guide.
+
+- Introduces the ``serverMonitoringMode`` connection URI option. To
+  learn more, see the :ref:`kotlin-sync-connection-options` guide.
+
+.. _kotlin-sync-version-5.0:
+
+What's New in 5.0
+-----------------
+
+New features of the 5.0 driver release include:
+
+- The ``KotlinSerializerCodecProvider`` constructor now accepts
+  ``serializersModule`` and ``bsonConfiguration`` objects:
+
+  .. code-block:: kotlin
+     
+     KotlinSerializerCodec.create(clazz.kotlin, serializersModule=serializersModule, bsonConfiguration=bsonConfiguration)
+  
+  This makes it easier to customize your configuration.
+
+- Fixes a Kotlin reflection bug that resulted in container type erasure.