diff --git a/Native/OpenDDSharp.IdlGenerator/csharp_cdr_generator.cpp b/Native/OpenDDSharp.IdlGenerator/csharp_cdr_generator.cpp
index 8a9bed74..db0e7181 100644
--- a/Native/OpenDDSharp.IdlGenerator/csharp_cdr_generator.cpp
+++ b/Native/OpenDDSharp.IdlGenerator/csharp_cdr_generator.cpp
@@ -929,10 +929,27 @@ csharp_cdr_generator::implement_to_cdr_field(AST_Type *field_type, std::string f
       break;
     }
     case AST_Decl::NT_struct: {
-      ret.append(indent);
-      ret.append("    writer.WriteBytes(");
-      ret.append(field_name);
-      ret.append(".ToCDR());\n");
+        ret.append("    if (");
+        ret.append(field_name);
+        ret.append(" == null)\n");
+
+        ret.append(indent);
+        ret.append("    {\n");
+
+        ret.append(indent);
+        ret.append("        ");
+        ret.append(field_name);
+        ret.append(" = new ");
+        ret.append(replaceString(std::string(field_type->full_name()), std::string("::"), std::string(".")));
+        ret.append("();\n");
+
+        ret.append(indent);
+        ret.append("    }\n");
+
+        ret.append(indent);
+        ret.append("    ");
+        ret.append(field_name);
+        ret.append(".ToCDR(writer);\n");
       break;
     }
     case AST_Decl::NT_string: {
diff --git a/Tests/OpenDDSharp.UnitTest/CodeGeneratorCdrWrapperTest.cs b/Tests/OpenDDSharp.UnitTest/CodeGeneratorCdrWrapperTest.cs
index 55477cda..883c5d66 100644
--- a/Tests/OpenDDSharp.UnitTest/CodeGeneratorCdrWrapperTest.cs
+++ b/Tests/OpenDDSharp.UnitTest/CodeGeneratorCdrWrapperTest.cs
@@ -4,6 +4,7 @@
 using System.Linq;
 using System.Threading;
 using CdrWrapper;
+using CdrWrapperInclude;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using OpenDDSharp.DDS;
 using OpenDDSharp.UnitTest.Helpers;
@@ -74,6 +75,84 @@ public void TestCleanup()
         #endregion
 
         #region Test Methods
+        /// <summary>
+        /// Test include idl files.
+        /// </summary>
+        [TestMethod]
+        [TestCategory(TEST_CATEGORY)]
+        public void TestInclude()
+        {
+            using var evt = new ManualResetEventSlim(false);
+
+            var test = new TestInclude();
+            Assert.AreEqual(typeof(IncludeStruct), test.IncludeField.GetType());
+            Assert.IsNotNull(test.IncludeField);
+            Assert.AreEqual(test.IncludeField.Message.GetType(), typeof(string));
+
+            var typeSupport = new TestIncludeTypeSupport();
+            var typeName = typeSupport.GetTypeName();
+            var ret = typeSupport.RegisterType(_participant, typeName);
+            Assert.AreEqual(ReturnCode.Ok, ret);
+
+            var topic = _participant.CreateTopic("TestTopic", typeName);
+            Assert.IsNotNull(topic);
+
+            var drQos = new DataReaderQos
+            {
+                Reliability =
+                {
+                    Kind = ReliabilityQosPolicyKind.ReliableReliabilityQos,
+                },
+            };
+            var dr = _subscriber.CreateDataReader(topic, drQos);
+            Assert.IsNotNull(dr);
+            var dataReader = new TestIncludeDataReader(dr);
+
+            var statusCondition = dr.StatusCondition;
+            Assert.IsNotNull(statusCondition);
+            statusCondition.EnabledStatuses = StatusKind.DataAvailableStatus;
+            TestHelper.CreateWaitSetThread(evt, statusCondition);
+
+            var dw = _publisher.CreateDataWriter(topic);
+            Assert.IsNotNull(dw);
+            var dataWriter = new TestIncludeDataWriter(dw);
+
+            Assert.IsTrue(dataWriter.WaitForSubscriptions(1, 5000));
+            Assert.IsTrue(dataReader.WaitForPublications(1, 5000));
+
+            test = new TestInclude
+            {
+                Id = "1",
+                IncludeField = new IncludeStruct
+                {
+                    Message = "Test",
+                },
+            };
+            ret = dataWriter.Write(test);
+            Assert.AreEqual(ReturnCode.Ok, ret);
+
+            ret = dataWriter.WaitForAcknowledgments(new Duration { Seconds = 5 });
+            Assert.AreEqual(ReturnCode.Ok, ret);
+
+            Assert.IsTrue(evt.Wait(1_500));
+
+            var received = new TestInclude();
+            var sampleInfo = new SampleInfo();
+            ret = dataReader.ReadNextSample(received, sampleInfo);
+            Assert.AreEqual(ReturnCode.Ok, ret);
+
+            Assert.AreEqual(test.Id, received.Id);
+            Assert.AreEqual(test.IncludeField.Message, received.IncludeField.Message);
+
+            dr.DeleteContainedEntities();
+            _subscriber.DeleteDataReader(dr);
+            _subscriber.DeleteContainedEntities();
+            _publisher.DeleteDataWriter(dw);
+            _publisher.DeleteContainedEntities();
+            _participant.DeleteTopic(topic);
+            _participant.DeleteContainedEntities();
+        }
+
         /// <summary>
         /// Test the code generated for the primitives types.
         /// </summary>
diff --git a/Tests/OpenDDSharp.UnitTest/OpenDDSharp.UnitTest.csproj b/Tests/OpenDDSharp.UnitTest/OpenDDSharp.UnitTest.csproj
index d1ac2ee2..ac15fbc7 100644
--- a/Tests/OpenDDSharp.UnitTest/OpenDDSharp.UnitTest.csproj
+++ b/Tests/OpenDDSharp.UnitTest/OpenDDSharp.UnitTest.csproj
@@ -62,8 +62,8 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.5.2" />
-    <PackageReference Include="MSTest.TestFramework" Version="3.5.2" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.6.1" />
+    <PackageReference Include="MSTest.TestFramework" Version="3.6.1" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/Tests/TestIdlCdr/IDL/Test.idl b/Tests/TestIdlCdr/IDL/Test.idl
index e591f60b..017fcbea 100644
--- a/Tests/TestIdlCdr/IDL/Test.idl
+++ b/Tests/TestIdlCdr/IDL/Test.idl
@@ -1,3 +1,5 @@
+#include "TestInclude.idl"
+
 module CdrWrapper {
 
     const short TEST_SHORT_CONST = -1;
@@ -149,6 +151,12 @@ module CdrWrapper {
         StructMultiArrayType StructMultiArrayField;
     };
 
+    @topic
+    struct TestInclude {
+        @key string Id;
+        CdrWrapperInclude::IncludeStruct IncludeField;
+    };
+
     @topic
     struct TestPrimitive {
         boolean BoolField;
diff --git a/Tests/TestIdlCdr/IDL/TestInclude.idl b/Tests/TestIdlCdr/IDL/TestInclude.idl
new file mode 100644
index 00000000..e276c221
--- /dev/null
+++ b/Tests/TestIdlCdr/IDL/TestInclude.idl
@@ -0,0 +1,8 @@
+module CdrWrapperInclude {
+
+    @topic
+    struct IncludeStruct {
+        @key string Message;
+    };
+
+};
\ No newline at end of file