This article discusses the challenges of developing a common performance measurement system for a collaborative supply chain. Through a case study of a supply chain in the fast moving consumer goods industry, the authors examine two potential collaborative performance measures - inventory levels and product availability. They find that inventory levels cannot reliably be measured collaboratively due to data limitations. Measuring product availability would require a complex information sharing system across the supply chain. The key challenges revealed include underlying data inconsistencies, the need to synchronize business processes, and determining an appropriate collaborative evaluation method.