As cooperation in a networked manner increases via various inter-organizational information systems (IOISs), it is important to choose appropriate IOISs for different types of organizations in the network environment. In this study, we analyzed customer-supplier relationships among organizations in five industries using social network analysis (SNA) methods and empirical data, aiming to help organizations strategically choose appropriate IOISs. Three types of customer-supplier networks were identified based on the network centralization comparison rate: customer-centric, supplier-centric and balanced networks. Based on the empirical findings in our analysis, we then propose strategies about how to choose appropriate IOISs for the firms in these networks and discuss the pros and cons of the choices. To the best of our knowledge, this is the first empirical research that applied SNA methods to study customer-supplier networks in the context of inter-organizational information systems.