This paper describes one organization's interpretation of the Patient-Centered Medical Home concept and the healthcare delivery system that has emerged from their participatory redesign initiative. Group Health, a large integrated healthcare system based in Seattle, Washington, USA initiated a Patient-Centered Medical Home care delivery system transformation in January 2007. Current theories and evidence about the Patient-Centered Medical Home (PCMH), the Chronic Care Model, and effective primary care were interpreted via a facilitated group process and translated into a core set of 5 system design principles. These design principles guided all subsequent system transformation activities. The central organizing principle is supporting and sustaining the patient-primary care physician relationship. The emergent PCMH healthcare delivery system comprises both opportunistic point-of-care and outreach components, many of which leverage and enhance the organization's health information and communication technologies.