1) The forms are no longer encapsulated and self sufficient 2) You have to pass object references around in order to address the objects inside the form and this can cause problems if those references are not cleaned up well. 3) You lose most of the benefits of object orientation 4) You have a truck load of prgs, or one big one with a truck load of procs in it. 5) You cannot see the code in the form designer or class designer 6) The class browser cannot show you the code 7) Form classes cannot be reused without also copying the supporting procs thus removing the advantage of subclassing versus cut and paste programming. 8) Every form must have the specific proc calls written into it, IOW using a form class with predefiend behaviors is not possible. Even deciding to change to using classes will mean essentially a complete rewrite.I'll let others add to the list.