Hi Nancy, and thanks.
Now I show further ignorance:

>If you want to use a field-level validation, you can create a stored procedure that does the search and then call that procedure from the field validation rule. Note, you probably want to first manually validate this in the table.
I think this is what I want. But I haven't done stored procedures before. does this involve code that does a seek? a select? (Duh)

>you might want to consider data entry from a CBO of a list of valid employees
I've done that with the small tables but the employee table makes for a long list.

>Also, you can add RI between the tables to ensure validity.
I did put RI on, but it only errors on save, I'm looking for ways to validate/trap errors immediately when the field is entered and lostfocus (I think).

>You don't ask about this, but I'd caution you to not use the employee number as a key field. There have been many discussions here about using surrogate vs. natural keys.
Thanks for the warning. I'll search for surrogate key discussions.