diff --git a/AutoDI.Fody.Tests/DerivedClassTests.cs b/AutoDI.Fody.Tests/DerivedClassTests.cs
new file mode 100644
index 0000000..7e4de19
--- /dev/null
+++ b/AutoDI.Fody.Tests/DerivedClassTests.cs
@@ -0,0 +1,71 @@
+using System.Reflection;
+using System.Threading.Tasks;
+using System.Xml.Linq;
+using AutoDI.AssemblyGenerator;
+using DerivedClassTestsNamespace;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace AutoDI.Fody.Tests
+{
+    [TestClass]
+    public class DerivedClassTests
+    {
+        private static Assembly _testAssembly;
+        private static IContainer _map;
+
+        [ClassInitialize]
+        public static async Task Initialize(TestContext context)
+        {
+            var gen = new Generator();
+
+            _testAssembly = (await gen.Execute()).SingleAssembly();
+
+            DI.Init(_testAssembly, builder =>
+            {
+                builder.ConfigureContainer<IContainer>(map =>
+                {
+                    _map = map;
+                });
+            });
+        }
+
+        [ClassCleanup]
+        public static void Cleanup()
+        {
+            DI.Dispose(_testAssembly);
+        }
+
+        [TestMethod]
+        [Description("Issue 121")]
+        public void CanExcludeDerivedClasses()
+        {
+            //TODO: Outstanding question of how to handle this...
+            var libraryClass = _testAssembly.Resolve<LibraryClass>();
+            Assert.AreEqual(nameof(LibraryClass), libraryClass?.GetType().Name);
+            var baseClass = _testAssembly.Resolve<MyBaseClass>();
+            Assert.AreEqual(nameof(MyBaseClass), baseClass?.GetType().Name);
+            var myClass = _testAssembly.Resolve<MyClass>();
+            Assert.AreEqual(nameof(MyClass), myClass?.GetType().Name);
+
+            var other = _testAssembly.Resolve<OtherBase>();
+            Assert.AreEqual(nameof(AllYourBase), other?.GetType().Name);
+        }
+    }
+}
+
+//<assembly />
+//<ref: AutoDI />
+//<weaver: AutoDI />
+namespace DerivedClassTestsNamespace
+{
+    public class LibraryClass { }
+
+    public class MyBaseClass : LibraryClass { }
+
+    public class MyClass : MyBaseClass { }
+
+    public class OtherBase { }
+
+    public class AllYourBase : OtherBase { }
+}
+//</assembly>
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