Aggregating demand may provide a route to realizing many of the benefits of outsourcing for those organizations too small to embrace it alone. Case studies of four joint service providers (JSPs) in the Australian public sector however highlight how the providers’ organizational and environmental context can influence success. Key differences that distinguish the more successful JSPs appear to relate to them having a greater focus on how to realize the promise of economies of scale and the capabilities and freedom to deliver – through process improvement, standardization and managing the required process of change in particular.