diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9d19c12..7b7bf64 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -21,6 +21,7 @@ jobs:
           7.0.x
           8.0.x
           9.0.x
+          10.0.x
 
     - name: Restore dependencies
       run: dotnet restore
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 04b836e..162d10d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 Represents the **NuGet** versions.
 
+## v5.7.0
+- *Enhancement:* Added `.NET10.0` support to all `UnitTestEx` packages.
+- *Enhancement:* Added `AssertNoNamedHeader` to the `HttpResponseMessageAssertor` to enable asserting that a named header is not present in the response.
+
 ## v5.6.3
 - *Fixed:* `TestSetUp` fixed to load _all_ assemblies on start up (versus selective) to ensure all `OneOffTestSetUpAttribute` implementations are executed prior to any test executions.
 - *Fixed:* Added `IJsonSerializer.Clone()` and `JsonElementComparerOptions.Clone` to ensure cross test contamination does not occur.
diff --git a/Common.targets b/Common.targets
index 5bd27e5..c84f041 100644
--- a/Common.targets
+++ b/Common.targets
@@ -1,6 +1,6 @@
 <Project>
 	<PropertyGroup>
-		<Version>5.6.3</Version>
+		<Version>5.7.0</Version>
 		<LangVersion>preview</LangVersion>
 		<Authors>Avanade</Authors>
 		<Company>Avanade</Company>
diff --git a/src/UnitTestEx.Azure.Functions/UnitTestEx.Azure.Functions.csproj b/src/UnitTestEx.Azure.Functions/UnitTestEx.Azure.Functions.csproj
index 7ec8186..edb620b 100644
--- a/src/UnitTestEx.Azure.Functions/UnitTestEx.Azure.Functions.csproj
+++ b/src/UnitTestEx.Azure.Functions/UnitTestEx.Azure.Functions.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx</RootNamespace>
     <Product>UnitTestEx</Product>
     <Title>UnitTestEx Azure Functions Test Extensions.</Title>
diff --git a/src/UnitTestEx.Azure.ServiceBus/UnitTestEx.Azure.ServiceBus.csproj b/src/UnitTestEx.Azure.ServiceBus/UnitTestEx.Azure.ServiceBus.csproj
index ef57da5..3893c71 100644
--- a/src/UnitTestEx.Azure.ServiceBus/UnitTestEx.Azure.ServiceBus.csproj
+++ b/src/UnitTestEx.Azure.ServiceBus/UnitTestEx.Azure.ServiceBus.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx</RootNamespace>
     <Product>UnitTestEx</Product>
     <Title>UnitTestEx Azure Functions Test Extensions.</Title>
diff --git a/src/UnitTestEx.MSTest/UnitTestEx.MSTest.csproj b/src/UnitTestEx.MSTest/UnitTestEx.MSTest.csproj
index 1dccf50..3f61882 100644
--- a/src/UnitTestEx.MSTest/UnitTestEx.MSTest.csproj
+++ b/src/UnitTestEx.MSTest/UnitTestEx.MSTest.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx.MSTest</RootNamespace>
 	  <Product>UnitTestEx MSTest</Product>
 	  <Title>UnitTestEx MSTest Test Extensions.</Title>
diff --git a/src/UnitTestEx.NUnit/UnitTestEx.NUnit.csproj b/src/UnitTestEx.NUnit/UnitTestEx.NUnit.csproj
index 3406a36..6957f22 100644
--- a/src/UnitTestEx.NUnit/UnitTestEx.NUnit.csproj
+++ b/src/UnitTestEx.NUnit/UnitTestEx.NUnit.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx.NUnit</RootNamespace>
 	  <Product>UnitTestEx NUnit</Product>
 	  <Title>UnitTestEx NUnit Test Extensions.</Title>
diff --git a/src/UnitTestEx.Xunit/UnitTestEx.Xunit.csproj b/src/UnitTestEx.Xunit/UnitTestEx.Xunit.csproj
index e8b0bb7..4a11daa 100644
--- a/src/UnitTestEx.Xunit/UnitTestEx.Xunit.csproj
+++ b/src/UnitTestEx.Xunit/UnitTestEx.Xunit.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx.Xunit</RootNamespace>
 	  <Product>UnitTestEx Xunit</Product>
 	  <Title>UnitTestEx Xunit Test Extensions.</Title>
diff --git a/src/UnitTestEx/Assertors/HttpResponseMessageAssertorBaseT.cs b/src/UnitTestEx/Assertors/HttpResponseMessageAssertorBaseT.cs
index e1842b4..593ec63 100644
--- a/src/UnitTestEx/Assertors/HttpResponseMessageAssertorBaseT.cs
+++ b/src/UnitTestEx/Assertors/HttpResponseMessageAssertorBaseT.cs
@@ -213,7 +213,7 @@ public TSelf AssertErrors(params ApiError[] errors)
 
             try
             {
-                val = GetValue<IDictionary<string, string[]>>(null); 
+                val = GetValue<IDictionary<string, string[]>>(null);
             }
             catch (Exception)
             {
@@ -295,5 +295,18 @@ public TSelf AssertNamedHeader(string name, params string[] values)
 
             return (TSelf)this;
         }
+
+        /// <summary>
+        /// Asserts that a response header does not exist with the specified <paramref name="name"/>.
+        /// </summary>
+        /// <param name="name">The header name.</param>
+        /// <returns>The <see cref="HttpResponseMessageAssertorBase{TSelf}"/> instance to support fluent-style method-chaining.</returns>
+        public TSelf AssertNoNamedHeader(string name)
+        {
+            if (Response.Headers.TryGetValues(name ?? throw new ArgumentNullException(nameof(name)), out var _))
+                Implementor.AssertFail($"The '{name}' header was found when it was expected to be absent.");
+
+            return (TSelf)this;
+        }
     }
 }
\ No newline at end of file
diff --git a/src/UnitTestEx/UnitTestEx.csproj b/src/UnitTestEx/UnitTestEx.csproj
index d6d7338..8a39f70 100644
--- a/src/UnitTestEx/UnitTestEx.csproj
+++ b/src/UnitTestEx/UnitTestEx.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net6.0;net7.0;net8.0;net9.0;net10.0</TargetFrameworks>
     <RootNamespace>UnitTestEx</RootNamespace>
     <Product>UnitTestEx</Product>
     <Title>UnitTestEx Test Extensions.</Title>
@@ -39,6 +39,12 @@
     <PackageReference Include="System.Text.Json" Version="9.0.0" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)' == 'net10.0'">
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.0" />
+    <PackageReference Include="System.Memory.Data" Version="10.0.0" />
+    <PackageReference Include="System.Text.Json" Version="10.0.0" />
+  </ItemGroup>
+
   <Import Project="..\..\Common.targets" />
 
 </Project>
diff --git a/tests/UnitTestEx.Api/UnitTestEx.Api.csproj b/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
index 907fc51..f8b3e15 100644
--- a/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
+++ b/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>
@@ -18,4 +18,8 @@
     <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="9.0.7" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)' == 'net10.0'">
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="10.0.0" />
+  </ItemGroup>
+
 </Project>
diff --git a/tests/UnitTestEx.MSTest.Test/UnitTestEx.MSTest.Test.csproj b/tests/UnitTestEx.MSTest.Test/UnitTestEx.MSTest.Test.csproj
index 19efd6d..365611a 100644
--- a/tests/UnitTestEx.MSTest.Test/UnitTestEx.MSTest.Test.csproj
+++ b/tests/UnitTestEx.MSTest.Test/UnitTestEx.MSTest.Test.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
     <IsPackable>false</IsPackable>
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <IsTestProject>true</IsTestProject>
diff --git a/tests/UnitTestEx.NUnit.Test/PersonControllerTest.cs b/tests/UnitTestEx.NUnit.Test/PersonControllerTest.cs
index 00f7c7b..a1436c2 100644
--- a/tests/UnitTestEx.NUnit.Test/PersonControllerTest.cs
+++ b/tests/UnitTestEx.NUnit.Test/PersonControllerTest.cs
@@ -320,7 +320,8 @@ public void Type_IActionResult()
 
             new Assertors.ValueAssertor<IActionResult>(test, iar, null)
                 .ToHttpResponseMessageAssertor(hr)
-                .AssertNamedHeader("X-Test", "Test");
+                .AssertNamedHeader("X-Test", "Test")
+                .AssertNoNamedHeader("X-Absent");
         }
     }
 }
\ No newline at end of file
diff --git a/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj b/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
index a33b8cc..19722fb 100644
--- a/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
+++ b/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
     <IsPackable>false</IsPackable>
     <LangVersion>preview</LangVersion>
   </PropertyGroup>
diff --git a/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj b/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
index c7a8c47..02ab924 100644
--- a/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
+++ b/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
     <IsPackable>false</IsPackable>
   </PropertyGroup>