The paper stresses the need to emphasize social relationships in system design especially in systems that cross enterprise boundaries in a changing environment. The paper describes these systems as a new class of systems – complex adaptive systems. It describes ways to model collaboration networks in such systems both as the drivers of change and as indicators of knowledge requirements. The paper defines a blueprint that for integrating business activities, network and knowledge into models that exhibit the characteristics of complex adaptive systems. It includes examples to illustrate the models.