diff --git a/BizHawk.MultiClient/Config.cs b/BizHawk.MultiClient/Config.cs
index 760138ab82..16d001cffb 100644
--- a/BizHawk.MultiClient/Config.cs
+++ b/BizHawk.MultiClient/Config.cs
@@ -27,6 +27,7 @@
         public string EmulatorPauseBinding = "Pause";
         public string FrameAdvanceBinding = "F";
         public string ScreenshotBinding = "F12";
+        public string ToggleFullscreenBinding = "LeftAlt+Return, RightAlt+Return";
 
         // SMS / GameGear Settings
         public bool SmsEnableFM = true;
diff --git a/BizHawk.MultiClient/MainForm.cs b/BizHawk.MultiClient/MainForm.cs
index e46cb1978c..3a8be1f59d 100644
--- a/BizHawk.MultiClient/MainForm.cs
+++ b/BizHawk.MultiClient/MainForm.cs
@@ -119,7 +119,8 @@ namespace BizHawk.MultiClient
         public static ControllerDefinition ClientControlsDef = new ControllerDefinition
         {
             Name = "Emulator Frontend Controls",
-            BoolButtons = { "Fast Forward", "Rewind", "Hard Reset", "Mode Flip", "Quick Save State", "Quick Load State", "Save Named State", "Load Named State", "Emulator Pause", "Frame Advance", "Screenshot" }
+            BoolButtons = { "Fast Forward", "Rewind", "Hard Reset", "Mode Flip", "Quick Save State", "Quick Load State", "Save Named State", "Load Named State", 
+                "Emulator Pause", "Frame Advance", "Screenshot", "Toggle Fullscreen" }
         };
 
         private void InitControls()
@@ -132,6 +133,7 @@ namespace BizHawk.MultiClient
             controls.BindMulti("Emulator Pause", Global.Config.EmulatorPauseBinding);
             controls.BindMulti("Frame Advance", Global.Config.FrameAdvanceBinding);
             controls.BindMulti("Screenshot", Global.Config.ScreenshotBinding);
+            controls.BindMulti("Toggle Fullscreen", Global.Config.ToggleFullscreenBinding);
             Global.ClientControls = controls;
 
             var smsControls = new Controller(SMS.SmsController);
@@ -363,6 +365,12 @@ namespace BizHawk.MultiClient
                 else Global.Sound.StartSound();
             }
 
+            if (Global.ClientControls["Toggle Fullscreen"])
+            {
+                Global.ClientControls.UnpressButton("Toggle Fullscreen");
+                ToggleFullscreen();
+            }
+
             if (EmulatorPaused == false || Global.ClientControls["Frame Advance"])
             {
                 CaptureRewindState();
@@ -846,8 +854,7 @@ namespace BizHawk.MultiClient
 
         private int lastWidth = -1;
         private int lastHeight = -1;
-
-
+               
         private void Render()
         {
             var video = Global.Emulator.VideoProvider;
@@ -893,6 +900,31 @@ namespace BizHawk.MultiClient
             }
         }
 
+        private bool InFullscreen = false;
+        private Point WindowedLocation;
+
+        public void ToggleFullscreen()
+        {
+            if (InFullscreen == false)
+            {
+                WindowedLocation = Location;
+                FormBorderStyle = FormBorderStyle.None;
+                WindowState = FormWindowState.Maximized;
+                MainMenuStrip.Visible = false;
+                PerformLayout();
+                Global.RenderPanel.Resized = true;
+                InFullscreen = true;
+            } else {
+                FormBorderStyle = FormBorderStyle.FixedSingle;
+                WindowState = FormWindowState.Normal;
+                MainMenuStrip.Visible = true;
+                Location = WindowedLocation;
+                PerformLayout();
+                FrameBufferResized();
+                InFullscreen = false;
+            }
+        }
+
         private void zoomMenuItem_Click(object sender, EventArgs e)
         {
             if (sender == x1MenuItem) Global.Config.TargetZoomFactor = 1;
diff --git a/BizHawk.MultiClient/RenderPanel.cs b/BizHawk.MultiClient/RenderPanel.cs
index b3cb6e0a6f..42d9faa0e7 100644
--- a/BizHawk.MultiClient/RenderPanel.cs
+++ b/BizHawk.MultiClient/RenderPanel.cs
@@ -156,6 +156,7 @@ namespace BizHawk.MultiClient
         {
             d3d = direct3D;
             backingControl = control;
+		    control.DoubleClick += (o, e) => Global.MainForm.ToggleFullscreen();
         }
 
         private void DestroyDevice()
@@ -223,13 +224,9 @@ namespace BizHawk.MultiClient
             Device.Clear(ClearFlags.Target, BackgroundColor, 1.0f, 0);
 
             // figure out scaling factor
-            int widthScale = backingControl.Size.Width / video.BufferWidth;
-            int heightScale = backingControl.Size.Height / video.BufferHeight;
-            int finalScale = Math.Min(widthScale, heightScale);
-
-            // center position
-            int xpos = (backingControl.Size.Width / 2) - (video.BufferWidth / 2);
-            int ypos = (backingControl.Size.Height / 2) - (video.BufferHeight / 2);
+            float widthScale = (float) backingControl.Size.Width /  video.BufferWidth;
+            float heightScale = (float) backingControl.Size.Height / video.BufferHeight;
+            float finalScale = Math.Min(widthScale, heightScale);
 
             Device.BeginScene();