diff --git a/bin/History.txt b/bin/History.txt
index 8249ce23..06b2a627 100644
--- a/bin/History.txt
+++ b/bin/History.txt
@@ -31,6 +31,7 @@ Changes:
                    (current memory address low byte)
      -memclear 7   Initialize memory to page address
                    (current memory address high byte)
+. [Feature #198] Alt-Return toggles full screen.
 . [Feature #199] Added the option to skip the reboot confirmation in the configuration.
 . [Feature #201] Added display of current Track/Sector for the floppy drives.
   - In 2x window mode the status is displayed below the drive LEDs.
diff --git a/source/Frame.cpp b/source/Frame.cpp
index 8647f23d..cee406d6 100644
--- a/source/Frame.cpp
+++ b/source/Frame.cpp
@@ -1550,6 +1550,10 @@ LRESULT CALLBACK FrameWndProc (
       break;
 
     case WM_SYSKEYDOWN:
+		KeybUpdateCtrlShiftStatus();
+		if (g_bAltKey && (wparam == VK_RETURN)) // NB. VK_RETURN = 0x0D; Normally WM_CHAR will be 0x0A but ALT key triggers as WM_SYSKEYDOWN
+			ScreenWindowResize(true);
+		else
       PostMessage(window,WM_KEYDOWN,wparam,lparam);
       if ((wparam == VK_F10) || (wparam == VK_MENU))	// VK_MENU == ALT Key
         return 0;