This article provides an overview of 20 years of professional experiences with developing and implementing a model for integrating behavioral health services into primary care. The Primary Care Behavioral Health (PCBH) model is designed to provide immediate access to behavioral care for a large number of primary care patients by positioning a behavioral health consultant in the exam room area to function as a core member of the primary care team. In an initial era of discovery, the authors were directly involved in developing and testing a variety of new approaches to providing behavioral health services in general medicine. In a second era focused on feasibility, the authors worked with Kaiser Permanente, the United States Air Force and Navy, the Veteran's Administration, and the Bureau of Primary Care to system test this innovative model of integrated care. Now in an era devoted to dissemination, the authors review the various roles formal research, system level quality improvement initiatives and stakeholder analysis play in promoting integrated care. The authors also describe current efforts to (1) create a tool that helps systems develop integration targets and (2) use the PCBH model as a platform for teaching medical residents and behavioral health providers to work together in a redesigned primary care team model.