Please help with the logic

[Del23]

I have a database that needs to assign multiple rows of table1 to a single row of table2. Here’s my dilemma: I need to make sure that only one row of table1 can be used in table2. (ie. I have a product list, table1, with only one of each product, and I want to assign more than one product to a customer, table2. No two customers can have the same product.)
How can I allow the user to choose from a list of available products for a single customer?

Thanks to all who try.

[Bob Fitz]

Not sure that I've understood what you are trying to do but have a look at the attached db. I think that the query used for the Row Source of the combo box called "ProdID" on the form may be the kind of thing you're looking for.