diff --git a/Jumpy.Shared/IWindow.cs b/Jumpy.Shared/IWindow.cs
new file mode 100644
index 0000000..4a9211d
--- /dev/null
+++ b/Jumpy.Shared/IWindow.cs
@@ -0,0 +1,7 @@
+using Microsoft.Xna.Framework;
+
+namespace Jumpy {
+  public interface IWindow {
+    void SetFullScreen(bool fullScreen, Game game, GraphicsDeviceManager graphics);
+  }
+}
diff --git a/Jumpy.Shared/Jumpy.Shared.projitems b/Jumpy.Shared/Jumpy.Shared.projitems
index 88dcb13..64df16b 100644
--- a/Jumpy.Shared/Jumpy.Shared.projitems
+++ b/Jumpy.Shared/Jumpy.Shared.projitems
@@ -9,6 +9,7 @@
     <Import_RootNamespace>Jumpy.Shared</Import_RootNamespace>
   </PropertyGroup>
   <ItemGroup>
+    <Compile Include="$(MSBuildThisFileDirectory)IWindow.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)KeyboardInput.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)JumpyGame.cs" />
   </ItemGroup>
diff --git a/Jumpy.Shared/JumpyGame.cs b/Jumpy.Shared/JumpyGame.cs
index 36901c1..65e5d20 100644
--- a/Jumpy.Shared/JumpyGame.cs
+++ b/Jumpy.Shared/JumpyGame.cs
@@ -10,6 +10,8 @@ namespace Jumpy {
     SpriteBatch spriteBatch;
     SpriteFont font;
     KeyboardInput keyboardInput = new KeyboardInput();
+    bool fullScreen = false;
+    IWindow window;
 
     public JumpyGame() {
       graphics = new GraphicsDeviceManager(this);
@@ -18,6 +20,8 @@ namespace Jumpy {
 
     // Performs initialization that's needed before starting to run.
     protected override void Initialize() {
+      window = (IWindow) Services.GetService(typeof(IWindow));
+      window.SetFullScreen(fullScreen, this, graphics);
       base.Initialize();
     }
 
@@ -37,10 +41,10 @@ namespace Jumpy {
       keyboardInput.Update();
       List<Keys> keysDown = keyboardInput.NewKeysDown();
 
-      //if (keysDown.Contains(Keys.F12))
-      //{
-      //    SetFullScreen(!fullScreen);
-      //}
+      if (keysDown.Contains(Keys.F12)) {
+        window.SetFullScreen(!fullScreen, this, graphics);
+        fullScreen = !fullScreen;
+      }
 
       if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed ||
           keysDown.Contains(Keys.Escape)) {