Paper describes an ongoing applied research project at KPN Telecom, the leading mobile and fixed telephony operator in the Netherlands. The project describes is aimed at developing a collaborative sales & operations planning business process at KPN that will support the ramp-up of new IP-based service offerings through KPN’s service supply network. Paper discusses root causes for why coordinating capacity and sales ramp-ups in the various stages of the chain is far more difficult in service than in manufacturing. Introduces workload as a key organising concept in collaborative supply chain coordination during ramp-ups. Describes project findings so far, which are still limited to conceptual simulation model development through group model-building workshops. Subsequent project results will be incorporated in the paper as these become available.