This paper addresses the need to incorporate the increasing trend of partnership formation among business firms into a framework for interorganizational systems. The existing frameworks for classifying interorganizational systems are either conceptually too complex to be readily applicable to IOS planning or too outdated to explain the emergence of numerous forms of global communication networks. Based upon two dimensions, namely value activity linkage and system support level, we propose a new IOS framework which classifies IOS into four types, including (1) operational cooperation, (2) resource pooling, (3) operational coordination, and (4) complementary partnership. We review select cases that fit into each IOS category and draw characteristics of systems of each category. The paper concludes with suggestions for applying the framework to the development of an IOS-enabled corporate strategy.