The purpose of this paper is to integrate social psychology and systems thinking by expanding Soft Systems Methodology (SSM) with Activity Theory (AT). Problems in the health care system are always very complex and Information Technology is usually considered to be a part of the solution. Our interest for research is in the area of elderly care, which consists of both health care and service efforts. These efforts are at some counties divided between two parties, municipality and county council. This implies a need for cooperation, communication and coordination. When this fails it affects the whole system. The problem situation must be seen as a holistic system problem but it is also essential to consider the individuals involved in the two systems and their socio-psychological environment. As a systems methodology, SSM, emphasizes the information processing and provides a methodology for solving the “soft” situations. AT, on the other hand, provides an approach for understanding the human activities in their context. With this perspective, we expanded SSM by integrating AT from two points and also introduced the concept of contradictions from Activity Theory as a way to compare the real world with the conceptual model. In the third stage of SSM, we use the six components of AT as a complement to the root definitions, CATWOE[1], given by Checkland. CATWOE provides comprehensive definitions about the system’s developmental variables, whereas the components in the AT model further focuses on the socio-psychological factors. In the fourth stage, we use the triangle model of AT as the basic element to build up a ‘conceptual model’. The focus of this paper is on the possibilities of combining SSM with AT, which resulted in a satisfying and reasonably effective method to analyze the home care service[2].