I have a MDI form that will have two child forms displayed. The first will be a sort of "menu" displaying a series of buttons on the left. I'd like the second form to butt up against the first form and fill the rest of the space. How do I control the positioning of the child forms within the MDI form? So far the first form displays correctly but regardless of what I try the second form overlaps the first as if it were being tiled.

I've had a problem like this before. If you do the following it will get round it:

1) Drop a panel control onto your mdi parent form, set the dock property to left and the border to 3d.

2) Drop a splitter control onto your mdi parent form - this will automatically dock to the left.

3) Create your 'menu' form in the left panel, rather than in a separate form.

4) Continue to use your 'main' form as you have been doing.

Once you do this, when you start your application, you'll see that the left window is preserved, and can even be resized through using the splitter.

Hope this gets you where you want to go!