We present a model of the process of job design that attempts to develop theory in five ways. First, critical variables in the model include performance, perceived competence, trust, knowledge and self-efficacy. Second, job design is proposed to be a dynamic and circular process, with the variables acting as both predictors and outcomes. Third, the process is seen, at least in part, as a social one, involving job-holders, supervisors and peers. Fourth, we identify some of the contingencies affecting the model. Finally, we specify the causal ordering of events and speculate on the nature of the time lags involved in the process. We make a number of model-based predictions and consider the implications of the model for theory, research and practice.