Hi Jim, thanks for the reply.

>If the user wants control over the values then it is not a purely unique >ID, it has meaning to the user. I would leave the user's ID alone and add >another field to be the PK for the table.

I agree with you, but unfortunately there is so much code and history in this application that the client would not want to take the risk of changing the way pks are allocated <s>.

Regards,
Alan