Here is a brief description of what I'm doing before asking the question.

I'm building a CRM type solution for tracking customer information -
contacts, quotes, etc. We have existing customer information that I can
download from our old, still in use, DOS system into an excel file that I can
import/link into our Access 2003 CRM Database. These customers have a unique
customer number: 12ACC1234 as an example. I figured I should use 12ACC1234
for a primary key so that when I update the excel file at some point in the
future, I can maintain integrity with the tracking CRM data we've added in
Access. If I assigned a generic primary key from Access (i.e. 1, 2, 3, 4)
that when I refresh the excel sheet with new customers entered into the old
DOS system, there would be a missmatch - customer number 12ACC1234 may have
had a primary key of 15 but now is 16 since we've entered a new customer in
the old DOS system that falls before customer 12ACC1234.

My dilema is a prospective customer that we want to create new in Access to
track CRM data but they won't as of yet be entered into the old DOS system -
only when we sell a product or service will a customer be given a customer
number such as 12ACC1234 in the old DOS system.

So the question is: am I faced with keeping two sets of tables of CRM data
and therfore two different primary keys? One based on existing clients
(12ACC1234) and one based on potentail clients (1,2,3,4)?

Thanks in advance from this novice user!
--
Dale, wishing we had one ERP database!