diff --git a/src/GitVersion.App.Tests/ArgumentParserTests.cs b/src/GitVersion.App.Tests/ArgumentParserTests.cs
index 42e7c36304..911c1f0812 100644
--- a/src/GitVersion.App.Tests/ArgumentParserTests.cs
+++ b/src/GitVersion.App.Tests/ArgumentParserTests.cs
@@ -636,6 +636,21 @@ public void AllowshallowTrueWhenDefined()
         arguments.AllowShallow.ShouldBe(true);
     }
 
+    [Test]
+    public void DiagTrueWhenDefined()
+    {
+        var arguments = this.argumentParser.ParseArguments("-diag");
+        arguments.Diag.ShouldBe(true);
+    }
+
+    [Test]
+    public void DiagAndLogToConsoleIsNotIgnored()
+    {
+        var arguments = this.argumentParser.ParseArguments("-diag -l console");
+        arguments.Diag.ShouldBe(true);
+        arguments.LogFilePath.ShouldBe("console");
+    }
+
     [Test]
     public void OtherArgumentsCanBeParsedBeforeNofetch()
     {
diff --git a/src/GitVersion.App/ArgumentParser.cs b/src/GitVersion.App/ArgumentParser.cs
index 1f85a1b3d2..d7b4df31bc 100644
--- a/src/GitVersion.App/ArgumentParser.cs
+++ b/src/GitVersion.App/ArgumentParser.cs
@@ -212,11 +212,7 @@ private static bool ParseSwitches(Arguments arguments, string? name, IReadOnlyLi
 
         if (name.IsSwitch("diag"))
         {
-            if (value?.IsTrue() != false)
-            {
-                arguments.Diag = true;
-            }
-
+            arguments.Diag = true;
             return true;
         }
 
diff --git a/src/GitVersion.App/ArgumentParserExtensions.cs b/src/GitVersion.App/ArgumentParserExtensions.cs
index 7d0dade040..286849c44b 100644
--- a/src/GitVersion.App/ArgumentParserExtensions.cs
+++ b/src/GitVersion.App/ArgumentParserExtensions.cs
@@ -73,7 +73,7 @@ public bool IsSwitch(string switchName)
 
         public bool ArgumentRequiresValue(int argumentIndex)
         {
-            var booleanArguments = new[] { "updateassemblyinfo", "ensureassemblyinfo", "nofetch", "nonormalize", "nocache", "allowshallow" };
+            var booleanArguments = new[] { "updateassemblyinfo", "ensureassemblyinfo", "nofetch", "nonormalize", "nocache", "allowshallow", "diag" };
 
             var argumentMightRequireValue = !booleanArguments.Contains(singleArgument[1..], StringComparer.OrdinalIgnoreCase);