Information systems (IS) integration has long been regarded as the result of various information technology (IT) related problems within the IS architecture and IT infrastructure. This study takes a new approach to examining the origins of IS integration problems from an organizational context perspective. Based on a 30-month longitudinal study at a 1,050 registered bed large teaching hospital, this paper shows that the complexity of organizational structural and cultural influence is a main factor that gives rise to hospital IS integration challenges. Theoretical and practical implications of this study are also discussed