diff --git a/src/AddIns/Misc/PackageManagement/Project/PackageManagement.csproj b/src/AddIns/Misc/PackageManagement/Project/PackageManagement.csproj
index d26639408e..61e8ad740e 100644
--- a/src/AddIns/Misc/PackageManagement/Project/PackageManagement.csproj
+++ b/src/AddIns/Misc/PackageManagement/Project/PackageManagement.csproj
@@ -125,6 +125,7 @@
     <Compile Include="Src\EnvDTE\FileCodeModelCodeElements.cs" />
     <Compile Include="Src\EnvDTE\FileCodeModelCodeNamespace.cs" />
     <Compile Include="Src\EnvDTE\FileCodeModelCodeNamespaceMembers.cs" />
+    <Compile Include="Src\EnvDTE\IClassExtensions.cs" />
     <Compile Include="Src\EnvDTE\ImplementedInterfacesOnClass.cs" />
     <Compile Include="Src\EnvDTE\IReturnTypeExtensions.cs" />
     <Compile Include="Src\EnvDTE\NamespaceName.cs" />
diff --git a/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/CodeType.cs b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/CodeType.cs
index 038093e591..eb7838dfc5 100644
--- a/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/CodeType.cs
+++ b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/CodeType.cs
@@ -2,6 +2,7 @@
 // This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
 
 using System;
+using System.Linq;
 using ICSharpCode.SharpDevelop.Dom;
 using ICSharpCode.SharpDevelop.Project;
 
@@ -72,15 +73,19 @@ namespace ICSharpCode.PackageManagement.EnvDTE
 		public virtual ProjectItem ProjectItem {
 			get {
 				if (ProjectContent.Project != null) {
-					return new ProjectItem((MSBuildBasedProject)ProjectContent.Project, Class);
+					return new ProjectItem(ProjectContent, Class);
 				}
 				return null;
 			}
 		}
 		
+		/// <summary>
+		/// Returns true if the current type matches the fully qualified name or any of its
+		/// base types are a match.
+		/// </summary>
 		public virtual bool IsDerivedFrom(string fullName)
 		{
-			throw new NotImplementedException();
+			return Class.IsDerivedFrom(fullName);
 		}
 	}
 }
diff --git a/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/IClassExtensions.cs b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/IClassExtensions.cs
new file mode 100644
index 0000000000..68d38b9081
--- /dev/null
+++ b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/IClassExtensions.cs
@@ -0,0 +1,43 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
+
+using System;
+using System.Linq;
+using ICSharpCode.SharpDevelop.Dom;
+
+namespace ICSharpCode.PackageManagement.EnvDTE
+{
+	public static class IClassExtensions
+	{
+		/// <summary>
+		/// Returns true if the class fully qualified name matches the name or
+		/// any class in the inheritance tree matches the name.
+		/// </summary>
+		public static bool IsDerivedFrom(this IClass c, string typeName)
+		{
+			if (c.FullyQualifiedName == typeName) {
+				return true;
+			}
+			
+			if (TypeNameMatchesBaseType(c.BaseType, typeName)) {
+				return true;
+			}
+			
+			return IsTypeInClassInheritanceTree(c, typeName);
+		}
+		
+		static bool TypeNameMatchesBaseType(IReturnType baseType, string typeName)
+		{
+			return
+				(baseType != null) &&
+				(baseType.FullyQualifiedName == typeName);
+		}
+		
+		static bool IsTypeInClassInheritanceTree(IClass c, string typeName)
+		{
+			return c
+				.ClassInheritanceTreeClassesOnly
+				.Any(inheritedClass => inheritedClass.FullyQualifiedName == typeName);
+		}
+	}
+}
diff --git a/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/ProjectItem.cs b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/ProjectItem.cs
index ebdaccfff8..747dee441b 100644
--- a/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/ProjectItem.cs
+++ b/src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/ProjectItem.cs
@@ -34,6 +34,11 @@ namespace ICSharpCode.PackageManagement.EnvDTE
 		{
 		}
 		
+		internal ProjectItem(IProjectContent projectContent, IClass c)
+			: this((MSBuildBasedProject)projectContent.Project, c)
+		{
+		}
+		
 		string GetKindFromFileProjectItemType()
 		{
 			if (IsDirectory) {
diff --git a/src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/CodeTypeTests.cs b/src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/CodeTypeTests.cs
index 0615a38957..4935c36043 100644
--- a/src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/CodeTypeTests.cs
+++ b/src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/CodeTypeTests.cs
@@ -46,7 +46,15 @@ namespace PackageManagement.Tests.EnvDTE
 		SDProject.FileProjectItem AddFileToProjectAndProjectContent(TestableProject project, string fileName)
 		{
 			helper.CompilationUnitHelper.SetFileName(fileName);
-			return project.AddFile(fileName);			
+			return project.AddFile(fileName);
+		}
+		
+		/// <summary>
+		/// Classes at the end of the array are at the top of the inheritance tree.
+		/// </summary>
+		void AddClassInheritanceTree(params string[] classNames)
+		{
+			helper.AddClassInheritanceTreeClassesOnly(classNames);
 		}
 		
 		[Test]
@@ -121,5 +129,70 @@ namespace PackageManagement.Tests.EnvDTE
 			
 			Assert.AreEqual("test.cs", item.Name);
 		}
+		
+		[Test]
+		public void IsDerivedFrom_ClassFullyQualifiedNameMatchesTypeNameBeingChecked_ReturnsTrue()
+		{
+			CreateProjectContent();
+			CreateClass("System.Web.Mvc.ActionResult");
+			CreateCodeType();
+			
+			bool derivedFrom = codeType.IsDerivedFrom("System.Web.Mvc.ActionResult");
+			
+			Assert.IsTrue(derivedFrom);
+		}
+		
+		[Test]
+		public void IsDerivedFrom_ClassFullyQualifiedNameDoesNotMatcheTypeNameBeingChecked_ReturnsFalse()
+		{
+			CreateProjectContent();
+			CreateClass("TestClass");
+			AddClassInheritanceTree("System.Object");
+			CreateCodeType();
+			
+			bool derivedFrom = codeType.IsDerivedFrom("System.Web.Mvc.ActionResult");
+			
+			Assert.IsFalse(derivedFrom);
+		}
+		
+		[Test]
+		public void IsDerivedFrom_ClassBaseTypeFullyQualifiedNameMatchesTypeName_ReturnsTrue()
+		{
+			CreateProjectContent();
+			CreateClass("CustomActionResult");
+			helper.AddBaseTypeToClass("System.Web.Mvc.ActionResult");
+			CreateCodeType();
+			
+			bool derivedFrom = codeType.IsDerivedFrom("System.Web.Mvc.ActionResult");
+			
+			Assert.IsTrue(derivedFrom);
+		}
+		
+		[Test]
+		public void IsDerivedFrom_ClassHasTypeInClassInheritanceTreeButNotImmediateBaseType_ReturnsTrue()
+		{
+			CreateProjectContent();
+			CreateClass("CustomActionResult");
+			AddClassInheritanceTree("CustomActionResultBase", "System.Web.Mvc.ActionResult");
+			CreateCodeType();
+			
+			bool derivedFrom = codeType.IsDerivedFrom("System.Web.Mvc.ActionResult");
+			
+			Assert.IsTrue(derivedFrom);
+		}
+		
+		[Test]
+		public void IsDerivedFrom_ClassHasClassInInheritanceTreeButNotImmediateParentAndClassBaseTypePropertyIsNotNull_ReturnsTrue()
+		{
+			CreateProjectContent();
+			CreateClass("CustomActionResult");
+			helper.AddBaseTypeToClass("CustomActionResultBase");
+			AddClassInheritanceTree("CustomActionResultBase", "System.Web.Mvc.ActionResult");
+			CreateCodeType();
+			
+			bool derivedFrom = codeType.IsDerivedFrom("System.Web.Mvc.ActionResult");
+			
+			Assert.IsTrue(derivedFrom);
+		}
 	}
 }
diff --git a/src/AddIns/Misc/PackageManagement/Test/Src/Helpers/ClassHelper.cs b/src/AddIns/Misc/PackageManagement/Test/Src/Helpers/ClassHelper.cs
index 55353ee3c7..124e4853a2 100644
--- a/src/AddIns/Misc/PackageManagement/Test/Src/Helpers/ClassHelper.cs
+++ b/src/AddIns/Misc/PackageManagement/Test/Src/Helpers/ClassHelper.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using ICSharpCode.SharpDevelop.Dom;
 using Rhino.Mocks;
 
@@ -66,13 +67,18 @@ namespace PackageManagement.Tests.Helpers
 			Class.Stub(c => c.BaseTypes).Return(baseTypes);
 		}
 		
-		IReturnType CreateBaseType(IClass baseTypeClass, string baseTypeFullName, string baseTypeDotNetName)
+		ReturnTypeHelper CreateBaseTypeHelper(IClass baseTypeClass, string baseTypeFullName, string baseTypeDotNetName)
 		{
 			var returnTypeHelper = new ReturnTypeHelper();
 			returnTypeHelper.CreateReturnType(baseTypeFullName);
 			returnTypeHelper.AddUnderlyingClass(baseTypeClass);
 			returnTypeHelper.AddDotNetName(baseTypeDotNetName);
-			return returnTypeHelper.ReturnType;
+			return returnTypeHelper;
+		}
+		
+		IReturnType CreateBaseType(IClass baseTypeClass, string baseTypeFullName, string baseTypeDotNetName)
+		{
+			return CreateBaseTypeHelper(baseTypeClass, baseTypeFullName, baseTypeDotNetName).ReturnType;
 		}
 		
 		public void AddClassToClassBaseTypes(string fullName)
@@ -185,5 +191,28 @@ namespace PackageManagement.Tests.Helpers
 		{
 			Class.Stub(c => c.DotNetName).Return(className);
 		}
+		
+		/// <summary>
+		/// Classes at the end of the array are at the top of the inheritance tree.
+		/// </summary>
+		public void AddClassInheritanceTreeClassesOnly(params string[] classNames)
+		{
+			List<IClass> classes = CreateClassInheritanceTree(classNames);
+			Class.Stub(c => c.ClassInheritanceTreeClassesOnly).Return(classes);
+		}
+		
+		List<IClass> CreateClassInheritanceTree(string[] classNames)
+		{
+			return classNames
+				.Select(name => CreateClassHelperWithPublicClass(name).Class)
+				.ToList();
+		}
+		
+		ClassHelper CreateClassHelperWithPublicClass(string name)
+		{
+			var classHelper = new ClassHelper();
+			classHelper.CreatePublicClass(name);
+			return classHelper;
+		}
 	}
 }