diff --git a/src/Main/Base/Project/Dom/ClassBrowser/BaseTypesTreeNode.cs b/src/Main/Base/Project/Dom/ClassBrowser/BaseTypesTreeNode.cs
new file mode 100644
index 0000000000..db675a83f6
--- /dev/null
+++ b/src/Main/Base/Project/Dom/ClassBrowser/BaseTypesTreeNode.cs
@@ -0,0 +1,48 @@
+// 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;
+
+namespace ICSharpCode.SharpDevelop.Dom.ClassBrowser
+{
+	/// <summary>
+	/// Description of BaseTypesTreeNode.
+	/// </summary>
+	public class BaseTypesTreeNode : ModelCollectionTreeNode
+	{
+		ITypeDefinitionModel definition;
+		string text;
+		
+		public BaseTypesTreeNode(ITypeDefinitionModel definition)
+		{
+			if (definition == null)
+				throw new ArgumentNullException("definition");
+			this.definition = definition;
+			this.text = SD.ResourceService.GetString("MainWindow.Windows.ClassBrowser.BaseTypes");
+		}
+
+		protected override IModelCollection<object> ModelChildren {
+			get {
+				return definition.BaseTypes;
+			}
+		}
+
+		protected override System.Collections.Generic.IComparer<ICSharpCode.TreeView.SharpTreeNode> NodeComparer {
+			get {
+				return NodeTextComparer;
+			}
+		}
+		
+		public override object Text {
+			get {
+				return text;
+			}
+		}
+		
+		public override object Icon {
+			get {
+				return SD.ResourceService.GetImageSource("Icons.16x16.OpenFolderBitmap");
+			}
+		}
+	}
+}
diff --git a/src/Main/Base/Project/Dom/ClassBrowser/TypeDefinitionTreeNode.cs b/src/Main/Base/Project/Dom/ClassBrowser/TypeDefinitionTreeNode.cs
index aaab2f62ac..0ceddedf8b 100644
--- a/src/Main/Base/Project/Dom/ClassBrowser/TypeDefinitionTreeNode.cs
+++ b/src/Main/Base/Project/Dom/ClassBrowser/TypeDefinitionTreeNode.cs
@@ -54,6 +54,12 @@ namespace ICSharpCode.SharpDevelop.Dom.ClassBrowser
 			}
 		}
 		
+		protected override void LoadChildren()
+		{
+			base.LoadChildren();
+			Children.Insert(0, new BaseTypesTreeNode(definition));
+		}
+		
 		public override void ActivateItem(System.Windows.RoutedEventArgs e)
 		{
 			var target = definition.Resolve();
diff --git a/src/Main/Base/Project/Dom/ITypeDefinitionModel.cs b/src/Main/Base/Project/Dom/ITypeDefinitionModel.cs
index 62934f4576..2f6009fd7f 100644
--- a/src/Main/Base/Project/Dom/ITypeDefinitionModel.cs
+++ b/src/Main/Base/Project/Dom/ITypeDefinitionModel.cs
@@ -17,6 +17,7 @@ namespace ICSharpCode.SharpDevelop.Dom
 		string Namespace { get; }
 		TypeKind TypeKind { get; }
 		IModelCollection<ITypeDefinitionModel> NestedTypes { get; }
+		IModelCollection<ITypeDefinitionModel> BaseTypes { get; }
 		IModelCollection<IMemberModel> Members { get; }
 		
 		IEnumerable<DomRegion> GetPartRegions();
diff --git a/src/Main/Base/Project/ICSharpCode.SharpDevelop.csproj b/src/Main/Base/Project/ICSharpCode.SharpDevelop.csproj
index 91a1577bd1..f55fdd6cfd 100644
--- a/src/Main/Base/Project/ICSharpCode.SharpDevelop.csproj
+++ b/src/Main/Base/Project/ICSharpCode.SharpDevelop.csproj
@@ -86,6 +86,7 @@
     <Compile Include="Designer\TypeResolutionService.cs" />
     <Compile Include="Dom\ClassBrowser\AssemblyLoadErrorTreeNode.cs" />
     <Compile Include="Dom\ClassBrowser\AssemblyTreeNode.cs" />
+    <Compile Include="Dom\ClassBrowser\BaseTypesTreeNode.cs" />
     <Compile Include="Dom\ClassBrowser\ClassBrowserTreeView.cs" />
     <Compile Include="Dom\ClassBrowser\IClassBrowser.cs" />
     <Compile Include="Dom\ClassBrowser\MemberTreeNode.cs" />
diff --git a/src/Main/SharpDevelop/Dom/ClassBrowser/ClassBrowserPad.cs b/src/Main/SharpDevelop/Dom/ClassBrowser/ClassBrowserPad.cs
index 1c536d2306..af585b8603 100644
--- a/src/Main/SharpDevelop/Dom/ClassBrowser/ClassBrowserPad.cs
+++ b/src/Main/SharpDevelop/Dom/ClassBrowser/ClassBrowserPad.cs
@@ -149,17 +149,21 @@ namespace ICSharpCode.SharpDevelop.Dom.ClassBrowser
 		
 		void AssemblyListCollectionChanged(IReadOnlyCollection<IAssemblyModel> removedItems, IReadOnlyCollection<IAssemblyModel> addedItems)
 		{
-			foreach (var assembly in addedItems) {
-				// Add this assembly to current workspace
-				if (activeWorkspace != null) {
-					activeWorkspace.AssemblyFiles.Add(assembly.Context.Location);
+			if (addedItems != null) {
+				foreach (var assembly in addedItems) {
+					// Add this assembly to current workspace
+					if (activeWorkspace != null) {
+						activeWorkspace.AssemblyFiles.Add(assembly.Context.Location);
+					}
 				}
 			}
 			
-			foreach (var assembly in removedItems) {
-				// Add this assembly to current workspace
-				if (activeWorkspace != null) {
-					activeWorkspace.AssemblyFiles.Remove(assembly.Context.Location);
+			if (removedItems != null) {
+				foreach (var assembly in removedItems) {
+					// Add this assembly to current workspace
+					if (activeWorkspace != null) {
+						activeWorkspace.AssemblyFiles.Remove(assembly.Context.Location);
+					}
 				}
 			}
 			
diff --git a/src/Main/SharpDevelop/Dom/TypeDefinitionModel.cs b/src/Main/SharpDevelop/Dom/TypeDefinitionModel.cs
index 20df0cead5..d2aa244ebe 100644
--- a/src/Main/SharpDevelop/Dom/TypeDefinitionModel.cs
+++ b/src/Main/SharpDevelop/Dom/TypeDefinitionModel.cs
@@ -270,6 +270,44 @@ namespace ICSharpCode.SharpDevelop.Dom
 		}
 		#endregion
 		
+		#region Base Types collection
+		NestedTypeDefinitionModelCollection baseTypes;
+		
+		IList<IUnresolvedTypeDefinition> GetBaseTypes(IUnresolvedTypeDefinition definition)
+		{
+			var compilation = context.GetCompilation();
+			if (compilation != null) {
+				var typeResolveContext = new SimpleTypeResolveContext(compilation.MainAssembly).WithCurrentTypeDefinition(Resolve());
+				var baseTypeList = new List<IUnresolvedTypeDefinition>();
+				foreach (var baseTypeRef in definition.BaseTypes) {
+					var resolvedTypeDefinition = baseTypeRef.Resolve(typeResolveContext).GetDefinition();
+					if (resolvedTypeDefinition != null) {
+						baseTypeList.Add(resolvedTypeDefinition.Parts[0]);
+					}
+				}
+				
+				return baseTypeList;
+			}
+			
+			return null;
+		}
+		
+		public IModelCollection<ITypeDefinitionModel> BaseTypes {
+			get {
+				if (baseTypes == null) {
+					baseTypes = new NestedTypeDefinitionModelCollection(context);
+					foreach (var part in parts) {
+						var baseTypeList = GetBaseTypes(part);
+						if (baseTypeList != null) {
+							baseTypes.Update(null, baseTypeList);
+						}
+					}
+				}
+				return baseTypes;
+			}
+		}
+		#endregion
+		
 		#region Update
 		/// <summary>
 		/// Updates this type definition model by replacing oldPart with newPart.
@@ -311,6 +349,9 @@ namespace ICSharpCode.SharpDevelop.Dom
 			if (nestedTypes != null) {
 				nestedTypes.Update(oldPart != null ? oldPart.NestedTypes : null, newPart != null ? newPart.NestedTypes : null);
 			}
+			if (baseTypes != null) {
+				baseTypes.Update(oldPart != null ? GetBaseTypes(oldPart) : null, newPart != null ? GetBaseTypes(newPart) : null);
+			}
 		}
 		#endregion