This study aims to develop an integration performance measurement model for each stage of information systems integration. In order to achieve the purpose of the research, first of all, the concepts of IS integration or consolidation are analyzed through theoretical and practical reviews. Also, a number of important studies of domestic and overseas cases about the stage models of IS integration or consolidation are critically reviewed. Second, we proposed three step stage model of is integration, Physical Integration stage, Application Integration stage, Service Integration stage, and Also proposed the performance measurement model for each stage of information systems integration. Third, especially in case of performance indicators and performance measurement methodology for physical integration stage are illustratively proposed, based upon the case of NCIA (National Computing Integration Agency) in Korea. This study provides the theoretical basis for reasonably deriving the stage model and performance measurement model for each stage of Information Systems Integration, and they are validating through investigating domestic and foreign practices. The results of this study are very likely to contribute to presenting the practical guideline for desirably implementing is integration or IS consolidation.