We are working on the Ariba upgrade for 9r1 and are actually trying to add a new functionality to a document in Buyer. We are trying to add a new approver each time a different cost center is used on a line item. The approver (s) must be in parallel. That being said, we know that some documents can contain more than 20 line items, with 20 different cost centers. How have other companies dealt with such an approval complex process? Any ideas on how we could simplify that process?