User involvement is recommended to analysts as a technique of successful system development, but as a process it is little understood. This case study compares four process models of user involvement-learning, conflict, political and garbage-can-with each other and with an empirical example of system development. Different models are seen as appropriate to explaining the nature of user involvement in different stages of development and contexts. Structural conditions and issues of power are shown to be decisive in the development of conflict and conflict resolution. A two-stage model of user involvement based on Robey and Farrow's work (1982) is proposed which distinguishes conflict development from conflict resolution.