In this paper we use multiple case studies and apply work system theory to them to better understand user satisfaction in each case. Based on the IS success model and the three case studies we conclude that beside the classic investigated objects information and technology as proposed by the IS success model also additional component of a work system influence user satisfaction. In particular we identified that work practices and also the relation between work practices, information and technologies have an influence on user satisfaction. We also revealed products/services and customers as potential drivers of user satisfaction and analyzed individual, environmental, strategical, and infrastructure characteristics as important contextual factors. Therefore, we suggest a work system success model for an extended understanding of user satisfaction that should better guide organizations when designing and implementing information systems.