diff --git a/extensions/manticore/Manticore.csproj b/extensions/manticore/Manticore.csproj
index 8f85eb88e67c..89414a33f298 100644
--- a/extensions/manticore/Manticore.csproj
+++ b/extensions/manticore/Manticore.csproj
@@ -242,6 +242,11 @@
                     SubType = "Code"
                     BuildAction = "Compile"
                 />
+                <File
+                    RelPath = "core\WindowMediator.cs"
+                    SubType = "Code"
+                    BuildAction = "Compile"
+                />
                 <File
                     RelPath = "defaults\bookmarks.xml"
                     BuildAction = "Content"
diff --git a/extensions/manticore/app.cs b/extensions/manticore/app.cs
index 50b0df38276f..bb8d28fba4da 100644
--- a/extensions/manticore/app.cs
+++ b/extensions/manticore/app.cs
@@ -45,29 +45,10 @@ namespace Silverstone.Manticore.App
   
   public class ManticoreApp
   {
-    // XXX Need to do something here more similar
-    //     to what mozilla does here for parameterized
-    //     window types.
-    private Hashtable mBrowserWindows;
-    private static BrowserWindow mMostRecentBrowserWindow = null;
-    public static BrowserWindow MostRecentBrowserWindow
-    {
-      get 
-      {
-        return mMostRecentBrowserWindow;
-      }
-      set 
-      {
-        mMostRecentBrowserWindow = value;
-      }
-    }
-        
     public ManticoreApp()
     {
-      mBrowserWindows = new Hashtable();
-
       if (!RestoreSession()) 
-        OpenBrowser();
+        BrowserWindow.OpenBrowser();
 
       Application.Run();
     }
@@ -91,8 +72,8 @@ namespace Silverstone.Manticore.App
     {
       if (ServiceManager.Preferences.GetIntPref("browser.homepage.mode") == 2) {
         bool isLastPageOnly = ServiceManager.Preferences.GetIntPref("browser.session.windowmode") == 0;
-        // XXX need to get all windows of type browser.
-        IEnumerator browsers = mBrowserWindows.Values.GetEnumerator();
+        WindowMediator wm = ServiceManager.WindowMediator;
+        IEnumerator browsers = wm.GetEnumeratorForType("BrowserWindow");
         int count = 0;
         while (browsers.MoveNext()) {
           if (isLastPageOnly && count > 0) {
@@ -131,7 +112,7 @@ namespace Silverstone.Manticore.App
        
           // Create a new browser with the applicable url at the applicable
           // location. 
-          BrowserWindow window = OpenBrowserWithURL(url);
+          BrowserWindow window = BrowserWindow.OpenBrowserWithURL(url);
           window.Location = new Point(x, y);
           window.Size = new Size(width, height);
         }
@@ -142,39 +123,10 @@ namespace Silverstone.Manticore.App
       return false;
     }
 
-    public void WindowClosed(BrowserWindow aWindow) 
-    {
-      if (mBrowserWindows.ContainsKey(aWindow.GetHashCode()))
-        mBrowserWindows.Remove(aWindow.GetHashCode());
-      
-      // When window count drops to zero, quit. 
-      // XXX - a little hacky for now, will eventually reflect
-      //       all windows. 
-      if (mBrowserWindows.Count == 0)
-        Quit();
-    }
-
-    // Opens and displays a new browser window
-    public BrowserWindow OpenBrowser()
-    {
-      BrowserWindow window = new BrowserWindow(this);
-      mBrowserWindows.Add(window.GetHashCode(), window);
-      window.Show();
-      return window;
-    }
-
-    public BrowserWindow OpenBrowserWithURL(String aURL)
-    {
-      BrowserWindow window = new BrowserWindow(this, aURL);
-      mBrowserWindows.Add(window.GetHashCode(), window);
-      window.Show();
-      return window;
-    }
-
     [STAThread]
     public static void Main(string[] args) 
     {
-      ManticoreApp app = new ManticoreApp();
+      ServiceManager.mApp = new ManticoreApp();
     }
   }
 }
diff --git a/extensions/manticore/bookmarks/BookmarksWindow.cs b/extensions/manticore/bookmarks/BookmarksWindow.cs
index 40ea6a5c8e8c..db972d2a90c3 100644
--- a/extensions/manticore/bookmarks/BookmarksWindow.cs
+++ b/extensions/manticore/bookmarks/BookmarksWindow.cs
@@ -44,6 +44,7 @@ namespace Silverstone.Manticore.Bookmarks
   using Silverstone.Manticore.Core;
   using Silverstone.Manticore.Toolkit;
   using Silverstone.Manticore.Bookmarks;
+  using Silverstone.Manticore.Browser;
 
   /// <summary>
 	/// Summary description for BookmarksWindow.
@@ -53,19 +54,20 @@ namespace Silverstone.Manticore.Bookmarks
     private System.Windows.Forms.StatusBar statusBar1;
     private System.Windows.Forms.StatusBarPanel statusBarPanel1;
     private BookmarksTreeView mBookmarksTree;
-		/// <summary>
-		/// Required designer variable.
-		/// </summary>
-		private System.ComponentModel.Container components = null;
 
     private BaseTreeBuilder mBuilder = null;
 
 		public BookmarksWindow()
 		{
-			//
-			// Required for Windows Form Designer support
-			//
-			InitializeComponent();
+      mType = "BookmarksWindow";
+      
+      Init();
+    }
+
+    protected void Init()
+    {
+      // Set up UI
+      InitializeComponent();
 
       // 
       // mBookmarksTree
@@ -83,24 +85,11 @@ namespace Silverstone.Manticore.Bookmarks
 
       Controls.Add(mBookmarksTree);
       mBookmarksTree.Build();
+
+      base.Init();
     }
-
-		/// <summary>
-		/// Clean up any resources being used.
-		/// </summary>
-		protected override void Dispose( bool disposing )
-		{
-			if( disposing )
-			{
-				if(components != null)
-				{
-					components.Dispose();
-				}
-			}
-			base.Dispose( disposing );
-		}
-
-		#region Windows Form Designer generated code
+    
+    #region Windows Form Designer generated code
 		/// <summary>
 		/// Required method for Designer support - do not modify
 		/// the contents of this method with the code editor.
@@ -152,7 +141,13 @@ namespace Silverstone.Manticore.Bookmarks
       ManticoreTreeNode node = mBookmarksTree.SelectedNode as ManticoreTreeNode;
       Bookmarks bmks = ServiceManager.Bookmarks;
       String bookmarkURL = bmks.GetBookmarkAttribute(node.Data as String, "url");
-      ManticoreApp.MostRecentBrowserWindow.LoadURL(bookmarkURL);
+      if (bookmarkURL != "") 
+      {
+        WindowMediator wm = ServiceManager.WindowMediator;
+        BrowserWindow window = wm.GetMostRecentWindow("BrowserWindow") as BrowserWindow;
+        if (window != null)
+          window.LoadURL(bookmarkURL);
+      }
     }
 
 	}
diff --git a/extensions/manticore/browser/browserwindow.cs b/extensions/manticore/browser/browserwindow.cs
index e22d7a89f2ac..e749aa0599ae 100644
--- a/extensions/manticore/browser/browserwindow.cs
+++ b/extensions/manticore/browser/browserwindow.cs
@@ -47,8 +47,6 @@ namespace Silverstone.Manticore.Browser
 
   public class BrowserWindow : ManticoreWindow, IController
   {
-    private System.ComponentModel.Container components;
-
     private MenuBuilder mMenuBuilder;
     private BrowserToolbarBuilder mToolbarBuilder;
 
@@ -57,7 +55,6 @@ namespace Silverstone.Manticore.Browser
     private StatusBar mStatusBar;
     private StatusBarPanel mProgressMeter;
     private StatusBarPanel mStatusPanel;
-    private ManticoreApp mApplication;
 
     private String mSessionURL = "";
 
@@ -66,49 +63,29 @@ namespace Silverstone.Manticore.Browser
     /// </summary>
     private String mTitle = "";
 
-    public BrowserWindow(ManticoreApp aApp)
+    public BrowserWindow()
     {
-      Init(aApp);
+      Init();
     }
 
-    public BrowserWindow(ManticoreApp aApp, String aURL)
+    public BrowserWindow(String aURL)
     {
       mSessionURL = aURL;
-      Init(aApp);
+      mType = "BrowserWindow";
+
+      Init();
     }
 
-    private void Init(ManticoreApp aApp)
+    protected void Init()
     {
-      mApplication = aApp;
-      mType = "Browser";
-
       // Set up UI
       InitializeComponent();
 
-      this.Closed += new EventHandler(OnFormClosed);
-      this.GotFocus += new EventHandler(OnSetFocus);
-    }
-
-    public void OnFormClosed(Object sender, EventArgs e) 
-    {
-      mApplication.WindowClosed(this);
-    }
-
-    public void OnSetFocus(Object sender, EventArgs e)
-    {
-      ManticoreApp.MostRecentBrowserWindow = this;
-    }
-
-    public override void Dispose()
-    {
-      base.Dispose();
-      components.Dispose();
+      base.Init();
     }
 
     private void InitializeComponent()
     {
-      this.components = new System.ComponentModel.Container();
-
       // XXX read these from a settings file
       this.Width = 640;
       this.Height = 480;
@@ -183,13 +160,24 @@ namespace Silverstone.Manticore.Browser
       }
     }
 
+    ///////////////////////////////////////////////////////////////////////////
+    // Window Creation
+    public static BrowserWindow OpenBrowser()
+    {
+      BrowserWindow window = new BrowserWindow();
+      window.Show();
+      return window;
+    }
+
+    public static BrowserWindow OpenBrowserWithURL(String aURL)
+    {
+      BrowserWindow window = new BrowserWindow(aURL);
+      window.Show();
+      return window;
+    }
 
     ///////////////////////////////////////////////////////////////////////////
     // Menu Command Handlers
-    public void OpenNewBrowser()
-    {
-      mApplication.OpenBrowser();
-    }
 
     public void Open()
     {
@@ -200,7 +188,8 @@ namespace Silverstone.Manticore.Browser
 
     public void Quit() 
     {
-      mApplication.Quit();
+      ManticoreApp app = ServiceManager.App;
+      app.Quit();
     }
 
     public Object currentLayoutEngine
@@ -233,8 +222,7 @@ namespace Silverstone.Manticore.Browser
 
     public Object OnNewWindow()
     {
-      // BrowserWindow window = mApplication.OpenNewBrowser();
-      // return window.currentLayoutEngine;
+      // XXX figure out what this does.
       return new Object();
     }
 
@@ -263,7 +251,7 @@ namespace Silverstone.Manticore.Browser
       switch (aCommand) 
       {
         case "file-new-window":
-          OpenNewBrowser();
+          OpenBrowser();
           break;
         case "file-open":
           Open();
diff --git a/extensions/manticore/core/ServiceManager.cs b/extensions/manticore/core/ServiceManager.cs
index b874d8330984..b20ce1aae5bb 100644
--- a/extensions/manticore/core/ServiceManager.cs
+++ b/extensions/manticore/core/ServiceManager.cs
@@ -34,6 +34,7 @@
 
 namespace Silverstone.Manticore.Core
 {
+  using Silverstone.Manticore.App;
 
   /// <summary>
   /// Access point to application-global services. 
@@ -70,5 +71,25 @@ namespace Silverstone.Manticore.Core
         return mBookmarks;
       }
     }
+ 
+    private static Silverstone.Manticore.Core.WindowMediator mWindowMediator = null;
+    public static Silverstone.Manticore.Core.WindowMediator WindowMediator
+    {
+      get 
+      {
+        if (mWindowMediator == null) 
+          mWindowMediator = new Silverstone.Manticore.Core.WindowMediator();
+        return mWindowMediator;
+      }
+    }
+
+    internal static Silverstone.Manticore.App.ManticoreApp mApp = null;
+    public static Silverstone.Manticore.App.ManticoreApp App
+    {
+      get 
+      {
+        return mApp;
+      }
+    }
   }
 }
\ No newline at end of file
diff --git a/extensions/manticore/core/WindowMediator.cs b/extensions/manticore/core/WindowMediator.cs
index d4d63ecefc96..8c851a54d776 100644
--- a/extensions/manticore/core/WindowMediator.cs
+++ b/extensions/manticore/core/WindowMediator.cs
@@ -2,7 +2,13 @@
 namespace Silverstone.Manticore.Core
 {
   using System;
-  
+  using System.Collections;
+
+  using Silverstone.Manticore.Toolkit;
+
+  // XXX - TODO: need to add logic to quit application when there are 
+  //             no more windows
+
   /// <summary>
 	/// Summary description for WindowMediator.
 	/// </summary>
@@ -10,6 +16,8 @@ namespace Silverstone.Manticore.Core
 	{
 		public WindowMediator()
 		{
+      mWindows = new Hashtable();
+      mRecentWindows = new Hashtable();
 		}
 
     /// <summary>
@@ -18,12 +26,60 @@ namespace Silverstone.Manticore.Core
     /// <returns></returns>
     public IEnumerator GetEnumerator()
     {
- 
+      return mWindows.GetEnumerator();
     }
 
-    // ManticoreWindow GetMostRecentWindow(String aType);
-    // void SetMostRecentWindow(ManticoreWindow);
-    // void RegisterWindow (ManticoreWindow);
-    // void UnregisterWindow (ManticoreWindow);
-	}
+    public IEnumerator GetEnumeratorForType(String aType)
+    {
+      return (mWindows[aType] as Hashtable).GetEnumerator();
+    }
+
+    protected Hashtable mWindows;
+    protected Hashtable mRecentWindows;
+
+    public ManticoreWindow GetMostRecentWindow(String aType)
+    {
+      if (mRecentWindows.ContainsKey(aType)) 
+        return mRecentWindows[aType] as ManticoreWindow;
+      return null;
+    }
+
+    public void SetMostRecentWindow(ManticoreWindow aWindow)
+    {
+      if (!mRecentWindows.ContainsKey(aWindow.Type))
+        mRecentWindows.Add(aWindow.Type, aWindow);
+      else
+        mRecentWindows[aWindow.Type] = aWindow;
+    }
+
+    public void RegisterWindow(ManticoreWindow aWindow)
+    {
+      if (!mWindows.ContainsKey(aWindow.Type))
+        mWindows[aWindow.Type] = new Hashtable();
+      Hashtable windowList = mWindows[aWindow.Type] as Hashtable;
+      windowList.Add(aWindow.GetHashCode(), aWindow);
+    }
+
+    public void UnregisterWindow(ManticoreWindow aWindow)
+    {
+      mWindows.Remove(aWindow.GetHashCode());
+      
+      // If this is the last window of a specific type, remove it from the window list
+      Hashtable windowsForType = mWindows[aWindow.Type] as Hashtable;
+      IEnumerator e = windowsForType.GetEnumerator();
+      e.MoveNext();
+      ManticoreWindow window = e.Current as ManticoreWindow;
+      if (window == null)
+        mWindows.Remove(aWindow.Type);
+      
+      ManticoreWindow mostRecentWindow = GetMostRecentWindow(aWindow.Type);
+      if (mostRecentWindow == window) 
+      {
+        if (window != null) 
+          SetMostRecentWindow(window);
+        else
+          mRecentWindows.Remove(aWindow.Type);
+      }
+    }
+  }
 }
diff --git a/extensions/manticore/toolkit/ManticoreWindow.cs b/extensions/manticore/toolkit/ManticoreWindow.cs
index af7753a5c2cc..c5718b15d17a 100644
--- a/extensions/manticore/toolkit/ManticoreWindow.cs
+++ b/extensions/manticore/toolkit/ManticoreWindow.cs
@@ -37,12 +37,14 @@ namespace Silverstone.Manticore.Toolkit
   using System;
   using System.Windows.Forms;
 
+  using Silverstone.Manticore.Core;
+
   /// <summary>
 	/// Top level window class
 	/// </summary>
 	public class ManticoreWindow : Form
 	{
-    protected internal String mType = "";
+    protected String mType = "";
 
     public String Type
     {
@@ -58,6 +60,32 @@ namespace Silverstone.Manticore.Toolkit
     public ManticoreWindow(String aType)
 		{
       mType = aType;
-		}
-	}
+    }
+
+    protected void Init()
+    {
+      WindowMediator wm = ServiceManager.WindowMediator;
+      wm.RegisterWindow(this);
+
+      this.Closed += new EventHandler(OnClosed);
+      this.Activated += new EventHandler(OnActivated);
+    }
+
+    public void OnClosed(Object sender, EventArgs e)
+    {
+      WindowMediator wm = ServiceManager.WindowMediator;
+      wm.UnregisterWindow(this);
+    }
+
+    public void OnActivated(Object sender, EventArgs e)
+    {
+      WindowMediator wm = ServiceManager.WindowMediator;
+      wm.SetMostRecentWindow(this);
+    }
+
+    public override void Dispose()
+    {
+      base.Dispose();
+    }
+  }
 }