Add a property to the form named oCurrentControl.

In the listboxes' Gotfocus events put this;

* Set form's current control
Thisform.oCurrentControl = This

In the form's destroy put;

* Clear the form's current control
This.oCurrentControl = NULL

In each command button's Click put;

* Your code here.

* followed by ...
Thisform.oCurrentControl.SetFocus()

This will allow the command buttons' click code to run without allowing the command buttons to ever actually get focus and will make the Enter key always fire the default button's click code.