>I am trying to make a single .exe which has several SDI forms in it, so the user would ALT-TAB from one to another (like how Word 2000 opens each document seperately).
>
>In my main.prg, I run another .prg that defines a new window, and I run menu code and then the main form in there. So I get a decent-looking SDI app.
>
>I have a button in this form, that is set to run another .prg that defines a new window, start a menu, and run another form. But it runs inside the calling SDI window, which makes a mess.
>
>Is it even possible to do what I want?

It maybe easier to have one main form (a container) to hold all your SDI forms. The main form would be "In Screen", while the service (SDI) form would be "Inside main form". The processes to service SDI transactions would be through the main form. IOW, the parent would manage communications between the children.

Another issue may be forcing focus to a particular child. We usually to this by embedding a zero width , zero height button. When our apps require focus switched to another child, the main form sets focus to our "zero" button and issues a KEYBOARD '{SPACE}' ( to "click" the button).

SDI - hmmm! - sounds like you dabbled with dbase V or VII!