I think that that Form.Activate method might do what you require. This brings a form to the front of Windows so that it would appear on top of anything that you have open. I have been using this from a notiify icon so that that double clicking the icon will bring the form to the z-order of all open windows apps. I assume this will work for threads within the same application but I haven't tried that (I'm not too familiar with threading code)

Bye.