diff --git a/ILSpy/App.xaml.cs b/ILSpy/App.xaml.cs
index 079b6d00f..39af423cb 100644
--- a/ILSpy/App.xaml.cs
+++ b/ILSpy/App.xaml.cs
@@ -18,9 +18,11 @@
 
 using System;
 using System.Diagnostics;
+using System.Threading;
 using System.Windows;
 using System.Windows.Documents;
 using System.Windows.Navigation;
+using System.Windows.Threading;
 
 namespace ICSharpCode.ILSpy
 {
@@ -33,11 +35,33 @@ namespace ICSharpCode.ILSpy
 		{
 			InitializeComponent();
 			
+			if (!Debugger.IsAttached) {
+				AppDomain.CurrentDomain.UnhandledException += ShowErrorBox;
+				Dispatcher.CurrentDispatcher.UnhandledException += Dispatcher_UnhandledException;
+			}
+			
 			EventManager.RegisterClassHandler(typeof(Window),
 			                                  Hyperlink.RequestNavigateEvent,
 			                                  new RequestNavigateEventHandler(Window_RequestNavigate));
 		}
 		
+		
+		static void Dispatcher_UnhandledException(object sender, DispatcherUnhandledExceptionEventArgs e)
+		{
+			Debug.WriteLine(e.Exception.ToString());
+			MessageBox.Show(e.Exception.ToString(), "Sorry, we crashed");
+			e.Handled = true;
+		}
+		
+		static void ShowErrorBox(object sender, UnhandledExceptionEventArgs e)
+		{
+			Exception ex = e.ExceptionObject as Exception;
+			if (ex != null) {
+				Debug.WriteLine(ex.ToString());
+				MessageBox.Show(ex.ToString(), "Sorry, we crashed");
+			}
+		}
+		
 		void Window_RequestNavigate(object sender, RequestNavigateEventArgs e)
 		{
 			Process.Start(e.Uri.ToString());
diff --git a/ILSpy/FilterSettings.cs b/ILSpy/FilterSettings.cs
index df6213104..5283c2d46 100644
--- a/ILSpy/FilterSettings.cs
+++ b/ILSpy/FilterSettings.cs
@@ -18,6 +18,8 @@
 
 using System;
 using System.ComponentModel;
+using System.Linq;
+using System.Xml.Linq;
 
 namespace ICSharpCode.ILSpy
 {
@@ -31,6 +33,21 @@ namespace ICSharpCode.ILSpy
 	/// </remarks>
 	public class FilterSettings : INotifyPropertyChanged
 	{
+		public FilterSettings(XElement element)
+		{
+			this.ShowInternalApi = (bool?)element.Element("ShowInternalAPI") ?? true;
+			this.Language = Languages.GetLanguage((string)element.Element("Language"));
+		}
+		
+		public XElement SaveAsXml()
+		{
+			return new XElement(
+				"FilterSettings",
+				new XElement("ShowInternalAPI", this.ShowInternalApi),
+				new XElement("Language", this.Language.Name)
+			);
+		}
+		
 		string searchTerm;
 		
 		public string SearchTerm {
@@ -50,7 +67,7 @@ namespace ICSharpCode.ILSpy
 			return text.IndexOf(searchTerm, StringComparison.OrdinalIgnoreCase) >= 0;
 		}
 		
-		bool showInternalApi = true;
+		bool showInternalApi;
 		
 		public bool ShowInternalApi {
 			get { return showInternalApi; }
@@ -62,7 +79,7 @@ namespace ICSharpCode.ILSpy
 			}
 		}
 		
-		Language language = Languages.AllLanguages[0];
+		Language language;
 		
 		public Language Language {
 			get { return language; }
diff --git a/ILSpy/ILSpy.csproj b/ILSpy/ILSpy.csproj
index d49ac75a4..0aaf7e826 100644
--- a/ILSpy/ILSpy.csproj
+++ b/ILSpy/ILSpy.csproj
@@ -89,6 +89,7 @@
     <Compile Include="Fusion.cs" />
     <Compile Include="GacInterop.cs" />
     <Compile Include="ILLanguage.cs" />
+    <Compile Include="ILSpySettings.cs" />
     <Compile Include="Language.cs" />
     <Compile Include="Images\Images.cs" />
     <Compile Include="Mono.Cecil.Rocks\MethodBodyRocks.cs" />
@@ -103,6 +104,7 @@
       <SubType>Code</SubType>
       <DependentUpon>MainWindow.xaml</DependentUpon>
     </Compile>
+    <Compile Include="SessionSettings.cs" />
     <Compile Include="SortableGridViewColumn.cs" />
     <Compile Include="TextView\CaretHighlightAdorner.cs" />
     <Compile Include="TextView\DecompilerTextView.cs" />
diff --git a/ILSpy/ILSpySettings.cs b/ILSpy/ILSpySettings.cs
new file mode 100644
index 000000000..10b46c836
--- /dev/null
+++ b/ILSpy/ILSpySettings.cs
@@ -0,0 +1,101 @@
+// Copyright (c) 2011 AlphaSierraPapa for the SharpDevelop Team
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+using System;
+using System.IO;
+using System.Linq;
+using System.Threading;
+using System.Xml;
+using System.Xml.Linq;
+
+namespace ICSharpCode.ILSpy
+{
+	/// <summary>
+	/// Manages IL Spy settings.
+	/// </summary>
+	public static class ILSpySettings
+	{
+		public static XElement LoadSettings(string section)
+		{
+			using (new MutexProtector(ConfigFileMutex)) {
+				try {
+					XDocument doc = XDocument.Load(GetConfigFile());
+					return doc.Root.Element(section) ?? new XElement(section);
+				} catch (IOException) {
+					return new XElement(section);
+				} catch (XmlException) {
+					return new XElement(section);
+				}
+			}
+		}
+		
+		public static void SaveSettings(XElement section)
+		{
+			using (new MutexProtector(ConfigFileMutex)) {
+				string config = GetConfigFile();
+				XDocument doc;
+				try {
+					doc = XDocument.Load(config);
+				} catch (IOException) {
+					// ensure the directory exists
+					Directory.CreateDirectory(Path.GetDirectoryName(config));
+					doc = new XDocument(new XElement("ILSpy"));
+				} catch (XmlException) {
+					doc = new XDocument(new XElement("ILSpy"));
+				}
+				doc.Root.SetAttributeValue("version", RevisionClass.Major + "." + RevisionClass.Minor + "." + RevisionClass.Build + "." + RevisionClass.Revision);
+				XElement existingElement = doc.Root.Element(section.Name);
+				if (existingElement != null)
+					existingElement.ReplaceWith(section);
+				else
+					doc.Root.Add(section);
+				doc.Save(config);
+			}
+		}
+		
+		public static string GetConfigFile()
+		{
+			return Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "ICSharpCode\\ILSpy.xml");
+		}
+		
+		const string ConfigFileMutex = "01A91708-49D1-410D-B8EB-4DE2662B3971";
+		
+		sealed class MutexProtector : IDisposable
+		{
+			Mutex mutex;
+			
+			public MutexProtector(string name)
+			{
+				bool createdNew;
+				this.mutex = new Mutex(true, name, out createdNew);
+				if (!createdNew) {
+					try {
+						mutex.WaitOne();
+					} catch (AbandonedMutexException) {
+					}
+				}
+			}
+			
+			public void Dispose()
+			{
+				mutex.ReleaseMutex();
+				mutex.Dispose();
+			}
+		}
+	}
+}
diff --git a/ILSpy/Language.cs b/ILSpy/Language.cs
index 3f8876d62..92ac30b07 100644
--- a/ILSpy/Language.cs
+++ b/ILSpy/Language.cs
@@ -18,6 +18,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using ICSharpCode.Decompiler;
 using Mono.Cecil;
 
@@ -80,5 +81,10 @@ namespace ICSharpCode.ILSpy
 			new ILLanguage(false),
 			new ILLanguage(true)
 		};
+		
+		public static Language GetLanguage(string name)
+		{
+			return AllLanguages.FirstOrDefault(l => l.Name == name) ?? AllLanguages.First();
+		}
 	}
 }
diff --git a/ILSpy/MainWindow.xaml b/ILSpy/MainWindow.xaml
index 1a63c6319..79b02d79c 100644
--- a/ILSpy/MainWindow.xaml
+++ b/ILSpy/MainWindow.xaml
@@ -3,8 +3,6 @@
 	x:Class="ICSharpCode.ILSpy.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:tv="clr-namespace:ICSharpCode.TreeView;assembly=ICSharpCode.TreeView"
 	xmlns:local="clr-namespace:ICSharpCode.ILSpy" xmlns:textView="clr-namespace:ICSharpCode.ILSpy.TextView"
 	Title="ILSpy"
-	Width="790"
-	Height="500"
 	MinWidth="250"
 	MinHeight="200"
 	UseLayoutRounding="True"
diff --git a/ILSpy/MainWindow.xaml.cs b/ILSpy/MainWindow.xaml.cs
index 2f6750a79..49501bcf8 100644
--- a/ILSpy/MainWindow.xaml.cs
+++ b/ILSpy/MainWindow.xaml.cs
@@ -17,6 +17,7 @@
 // DEALINGS IN THE SOFTWARE.
 
 using System;
+using System.Collections.Generic;
 using System.ComponentModel;
 using System.Diagnostics;
 using System.IO;
@@ -39,7 +40,7 @@ namespace ICSharpCode.ILSpy
 	{
 		AssemblyList assemblyList = new AssemblyList();
 		AssemblyListTreeNode assemblyListTreeNode;
-		FilterSettings filterSettings = new FilterSettings();
+		SessionSettings settings = new SessionSettings();
 		
 		static readonly System.Reflection.Assembly[] initialAssemblies = {
 			typeof(object).Assembly,
@@ -58,13 +59,20 @@ namespace ICSharpCode.ILSpy
 		
 		public MainWindow()
 		{
-			this.DataContext = filterSettings;
+			this.DataContext = settings.FilterSettings;
+			this.Left = settings.WindowBounds.Left;
+			this.Top = settings.WindowBounds.Top;
+			this.Width = settings.WindowBounds.Width;
+			this.Height = settings.WindowBounds.Height;
+			// TODO: validate bounds (maybe a screen was removed...)
+			this.WindowState = settings.WindowState;
+			
 			InitializeComponent();
 			decompilerTextView.mainWindow = this;
 			
 			assemblyListTreeNode = new AssemblyListTreeNode(assemblyList);
-			assemblyListTreeNode.FilterSettings = filterSettings.Clone();
-			filterSettings.PropertyChanged += new PropertyChangedEventHandler(filterSettings_PropertyChanged);
+			assemblyListTreeNode.FilterSettings = settings.FilterSettings.Clone();
+			settings.FilterSettings.PropertyChanged += new PropertyChangedEventHandler(filterSettings_PropertyChanged);
 			treeView.Root = assemblyListTreeNode;
 			assemblyListTreeNode.Select = SelectNode;
 			
@@ -75,6 +83,8 @@ namespace ICSharpCode.ILSpy
 				assemblyList.OpenAssembly(args[i]);
 			}
 			
+			SelectNode(FindNodeByPath(settings.ActiveTreeViewPath));
+			
 			#if DEBUG
 			AddDebugItemsToToolbar();
 			#endif
@@ -85,7 +95,7 @@ namespace ICSharpCode.ILSpy
 			// filterSettings is mutable; but the ILSpyTreeNode filtering assumes that filter settings are immutable.
 			// Thus, the main window will use one mutable instance (for data-binding), and assign a new clone to the ILSpyTreeNodes whenever the main
 			// mutable instance changes.
-			assemblyListTreeNode.FilterSettings = filterSettings.Clone();
+			assemblyListTreeNode.FilterSettings = settings.FilterSettings.Clone();
 			if (e.PropertyName == "Language") {
 				TreeView_SelectionChanged(null, null);
 			}
@@ -103,6 +113,33 @@ namespace ICSharpCode.ILSpy
 			}
 		}
 		
+		SharpTreeNode FindNodeByPath(string[] path)
+		{
+			if (path == null)
+				return null;
+			SharpTreeNode node = treeView.Root;
+			foreach (var element in path) {
+				if (node == null)
+					break;
+				node.EnsureLazyChildren();
+				node = node.Children.FirstOrDefault(c => c.ToString() == element);
+			}
+			return node;
+		}
+		
+		string[] GetPathForNode(SharpTreeNode node)
+		{
+			if (node == null)
+				return null;
+			List<string> path = new List<string>();
+			while (node.Parent != null) {
+				path.Add(node.ToString());
+				node = node.Parent;
+			}
+			path.Reverse();
+			return path.ToArray();
+		}
+		
 		#region Debugging CFG
 		#if DEBUG
 		void AddDebugItemsToToolbar()
@@ -213,7 +250,23 @@ namespace ICSharpCode.ILSpy
 		
 		void TreeView_SelectionChanged(object sender, SelectionChangedEventArgs e)
 		{
-			decompilerTextView.Decompile(filterSettings.Language, treeView.SelectedItems.OfType<ILSpyTreeNodeBase>());
+			decompilerTextView.Decompile(settings.FilterSettings.Language, treeView.SelectedItems.OfType<ILSpyTreeNodeBase>());
+		}
+		
+		protected override void OnStateChanged(EventArgs e)
+		{
+			base.OnStateChanged(e);
+			// store window state in settings only if it's not minimized
+			if (this.WindowState != System.Windows.WindowState.Minimized)
+				settings.WindowState = this.WindowState;
+		}
+		
+		protected override void OnClosing(CancelEventArgs e)
+		{
+			base.OnClosing(e);
+			settings.ActiveTreeViewPath = GetPathForNode(treeView.SelectedItem as SharpTreeNode);
+			settings.WindowBounds = this.RestoreBounds;
+			settings.Save();
 		}
 	}
 }
\ No newline at end of file
diff --git a/ILSpy/SessionSettings.cs b/ILSpy/SessionSettings.cs
new file mode 100644
index 000000000..47c8e681e
--- /dev/null
+++ b/ILSpy/SessionSettings.cs
@@ -0,0 +1,73 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under MIT X11 license (for details please see \doc\license.txt)
+
+using System;
+using System.ComponentModel;
+using System.Linq;
+using System.Windows;
+using System.Xml.Linq;
+
+namespace ICSharpCode.ILSpy
+{
+	/// <summary>
+	/// Per-session setting:
+	/// Loaded at startup; saved at exit.
+	/// </summary>
+	public class SessionSettings
+	{
+		public SessionSettings()
+		{
+			XElement doc = ILSpySettings.LoadSettings("SessionSettings");
+			
+			XElement filterSettings = doc.Element("FilterSettings");
+			if (filterSettings == null) filterSettings = new XElement("FilterSettings");
+			
+			this.FilterSettings = new FilterSettings(filterSettings);
+			
+			XElement activeTreeViewPath = doc.Element("ActiveTreeViewPath");
+			if (activeTreeViewPath != null) {
+				this.ActiveTreeViewPath = activeTreeViewPath.Elements().Select(e => (string)e).ToArray();
+			}
+			
+			this.WindowState = FromString((string)doc.Element("WindowState"), WindowState.Normal);
+			this.WindowBounds = FromString((string)doc.Element("WindowBounds"), new Rect(10, 10, 750, 550));
+		}
+		
+		public FilterSettings FilterSettings;
+		
+		public string[] ActiveTreeViewPath;
+		
+		public WindowState WindowState = WindowState.Normal;
+		public Rect WindowBounds;
+		
+		public void Save()
+		{
+			XElement doc = new XElement("SessionSettings");
+			doc.Add(this.FilterSettings.SaveAsXml());
+			if (this.ActiveTreeViewPath != null) {
+				doc.Add(new XElement("ActiveTreeViewPath", ActiveTreeViewPath.Select(p => new XElement("Node", p))));
+			}
+			doc.Add(new XElement("WindowState", ToString(this.WindowState)));
+			doc.Add(new XElement("WindowBounds", ToString(this.WindowBounds)));
+			ILSpySettings.SaveSettings(doc);
+		}
+		
+		static T FromString<T>(string s, T defaultValue)
+		{
+			if (s == null)
+				return defaultValue;
+			try {
+				TypeConverter c = TypeDescriptor.GetConverter(typeof(T));
+				return (T)c.ConvertFromInvariantString(s);
+			} catch (FormatException) {
+				return defaultValue;
+			}
+		}
+		
+		static string ToString<T>(T obj)
+		{
+			TypeConverter c = TypeDescriptor.GetConverter(typeof(T));
+			return c.ConvertToInvariantString(obj);
+		}
+	}
+}