This paper reports on the need for integration and different aspects of interoperability in CSCW. This is a part of our research towards investigating and developing an integrative framework for CSCW applications. The framework will enable different applications to communicate with each other to share information and to support organizational activities. It will be flexible enough to accommodate the various and varying needs of the user community. We discuss different types of integration and interoperability in CSCW and consider different models of CSCW systems. A framework for CSCW integration is presented. The framework includes ontological, coordination, user interface, security and transaction models. An example application scenario involving integration is given. The work is novel as no integrative framework for CSCW exists currently.