The task faced by a water supply system while handing over engineering services to a new provider poses challenges, including the additional strain on resources, the transfer of process management and adjusting to new organizational structures and communication channels. We helped the Dübendorf Water Supply Cooperative switch to a new engineering firm that will support the water supply company with operations and planning services for many years to come. We ensured an orderly handover with process development, legal advice and change management, among other things.