First of all, I am familiar with Access, but am definately not a Pro.

After doing some research, I am trying to get a cascading combo box to work on a form. The form is based off of the "Placings" table.

The form has two combo boxes, one that selects an "ExhibitorID" and the other that you can select a "ClassNo" from based on the "ExhibitorID" (i.e. if the EhibitorID is >500 only ClassNo 2000 to 9000 are available, but if ExhibitorID < 500 all ClassNo is available).

I am having problems with the design and concept, can anyone please help me?