Enterprise systems are information management systems that have broad business functional scope. They provide companies with the ability to improve information flows across the entire organisation enabling improved decision making and action. Although companies face numerous complexities in enterprise system implementations, examination of critical success factors (CSF) has provided insight into successful implementation practices. The main CSFs affecting enterprise system success are people related. In this paper we will identify these factors in the context of change management. A path model is developed incorporating I/O and psychology disciplines demonstrating individual contextual and implementation variables implicated in implementation success. Further, we argue that consideration of antecedents and interactions are essential for understanding change impacts and for development of an effective change management strategy.