Master Item- Import Items from multiples Systems

Summary

Master Item- Import Items from multiples Systems

Content

I need to interface items from different systems and each system has different item numbers.

I could have the same item number in different system and those are not the same item.

 Example

 Item number 123 = Pen (system = 1)

Item number 123 = Paper 8 x 11 (System  =2)

 We are planing to import items and PO from those system. The PO's interface includes the Item # so I don't know what to do.

 I want to keep the item number but the item number is unique. If i change the item number from one system, I need to develop some logic in the PO interface to get the new item number.