This document bases its discussions on user participation on the experience gained from two and a half years' practical work between Living Options In Practice and eight multi-agency Practice Teams throughout England, which worked to create comprehensive disability service systems. The following elements are discussed in the context of the project's commitment to a multi-agency `service development team' approach, and its focus on people with severe physical and sensory disabilities: defines user participation and describes some essential elements in `good practice' participation in service development; analyses key steps in the process of developing effective user participation; shares lessons from the eight practice Teams as they worked towards full participation of disabled people. The principles and guidance set out in this document, however, will also be of use to localities which are developing services in different ways and for different client groups.