Internal vs External Numbering Ranges

Hi guys,

Having worked in SAP for over 10 years, I have

usually recommended internal numbering ranges to my customers as much as was possible. However, I currently have a customer

that is bent upon using external numbering ranges for its material master records.

Can you guys provide me with your

thoughts on the pros/cons of using Internal versus External numbering scheme for material masters?

Some of the

obvious benefits of internal numbering system are that it is sequential, automatically generated, does not require

understanding/knowledge of the logic used to number materials, etc.

On the other hand however, internal numbers will

cause the maximum change to internal users, suppliers and customers of the organization. They are difficult to memorize as

there is no intelligence behind them, and will require a long drawn task of assigning new material numbers and maintaining a

cross-reference.

So what else can you guys contribute? Thanks in advance