Limitation in the representation of a client and its structure (its internal organization):

Hi,

Project'Or RIA is not devoted to describing the structure of an Enterprise.
So what you try to do is a bit borderline.

All you can possibly do is normalize names of client, and define one client per departement.
For instance : "CLT1 - DPTx", "CLT1 - DPTy", "CLT2 - DPTz" and so on.
Then you can use client code for some grouping (using same client code for all departement)

I hope this answers your question.
To be more accurate, it would be helpful to know why you need to describe the srtucture of the cleint enterprise.

Regards.