>OK, now I really DON'T understand. When I removed the >flushwindowbuffer statements the marquee does not display. I am using >WHILE FN StillDown : WEND, but still need to use flushwindowbuffer. It seems that the flushwindowbuffer statement is in the correct place. http://developer.apple.com/ReleaseNotes/Carbon/RN-HIToolbox/index.html Tips for Compatibility with Mac OS X 10.4 Window Manager "The Window Manager on Mac OS X has always flushed the window buffers of all visible windows during any call to the event loop, including calls to the StillDown, WaitMouseUp, and EventAvail APIs. These APIs have historically been fast, light-weight calls, and the addition of flushing in the Mac OS X implementation has been considered a drawback by some applications. We hope to address this issue in a future release of Mac OS X by changing the behavior of these APIs, but there is no behavioral change in Mac OS X 10.4. For compatibility with future versions of Mac OS X, we recommend that you do not rely on StillDown, WaitMouseUp, or EventAvail causing a window flush." IMPORTANT: "If your application has a tight loop that calls no event API except one of these three, which should be rare in a modern Carbon application, you can simply add an explicit call to QDFlushPortBuffer to flush the appropriate window." Which OS are you using? 10.5? PPC or Intel? Michele.