Dockable Window in Windows Forms

You've got a great range of answers already here, but I'll just add the comment that in questions like this it's a good idea to try and tell exactly what you want: if what you want is exactly the same as what Visual Studio provides: that is one thing; if what you want is simpler ... like just how to make a window stick to the edges of another window: that's a whole different question, so much simpler.

Personally, I use a third-party control suite (Lidor) to handle all my docking needs.

You already have an answer here which tells you how to do it in VB, and you accepted that answer: why are you asking this now ?

thanks, Bill