Integration and adaptation between an information system and the related business organisation is an important challenge for IS development project managers. Both IS research and software engineering research have contributed important lessons on integration, but at the practical level of IS development projects the processes of integration and mutual adaptation is less well understood. In this paper we apply a socio-technical perspective to analyze the integration of stakeholders and technical components, and we identify four generic integration patterns; Big Bang, Stakeholder Integration, Technical Integration and Socio-Technical Integration. Three case studies of iterative software development projects are used to illustrate the patterns. These illustrations highlight the management challenges of iterative integration. While early integration increases the likelihood of implementation success, it also increases the complexity of the projects. For practitioners the four integration patterns represent an analytical tool for planning iterative systems development projects. For IS research the four integration patterns are a contribution to a vocabulary for describing socio-technical integration.