I've been asked to create a database for signups in limited capacity activities; once the 25 seats are filled, the activity no longer appears as a choice. Is this possible?

Create a record for each activity in the activities table, a record for each person signing up in a people table, and create a join table that states which people are signed up for each activity.

Then create a calculation field in the activities table which uses the Count() function to count all of the related records in the join table. Another calculation could then be used to set a flag when the count field is >25. You could also do this in one calculation if you weren't going to use the Count() field for anything else.

Then wherever your value list of activities is used, just set up the relationship to only show values where the flag is not set.

Thank you very much. I appreciate your help.