Community-oriented primary care (COPC), a 50-year-old widely applied innovative approach to primary care development, seems to be the same combination of public health and general practice perspectives currently sought in the formation of primary care trusts in Britain's NHS. The article reviews the experience of implementing COPC methods, the outcomes, and the applicability to and implications for primary care policy, taking the current British reforms as an example. The COPC model has been developed mainly in underserved populations to integrate public health objectives and primary care through interdisciplinary approaches, with active involvement of the target population. COPC methods are time consuming, can create problems with professional boundaries, and are vulnerable to socioeconomic changes. They can also deliver complex packages of care for target populations, particularly in poor areas underserved by traditional medical services. British primary care reforms may be seen as an unplanned, uncontrolled, nationwide experiment in applying COPC methods. They differ from COPC as applied elsewhere because change has been introduced from above rather than below, into a well-developed primary care system rather than underserved communities. International experience suggests the need for attention to factors promoting and impeding success and to reliable outcome measures. If this experiment succeeds, COPC methodology may facilitate similar changes in other health care systems.