Numerous eHealth projects and efforts to establish inter-organizational communication and to build up regional health care networks could be observed in the last ten years. Nevertheless the success of such efforts is profoundly different. The aim of this paper is to introduce the lately started regional initiative eHealth.Braunschweig compounding of the major health care players (hospitals, physician offices, nursing services and nursing homes) in the region of Braunschweig, participants from research institutions and industry. We propose in this paper the main goals of the regional initiative eHealth.Braunschweig, its constitution and major approaches. Based on respective literature and our former projects as well as experiences in this field we discuss our vision of a patient-oriented cooperative health care by depicting regional distinctions, identifying the major domain fields in this context and discussing the architectural challenges for the regional health care network eHealth.Braunschweig. In our view this work can be considered as a systematical approach to the establishment of regional health care networks with lasting and sustainable effects on patient-centered health care in a region.