St. Martins Practice in Leeds provides secondary care addiction services in a primary care setting to approximately 150 substance misusers per year. It combines some benefits of a specialist service with the attributes of primary care: continuity, holism, accessibility and cost-effectiveness. It is integrated into a city-wide development strategy which encompasses a range of service styles tailored to local needs and capacity within primary care. The program is accessed by traditionally hard-to-reach population groups, and user satisfaction is high. The service is effective in delivering improved health outcomes through a range of interventions aimed at harm reduction, stabilization, and abstinence. The primary care setting offers "added value," for instance, ensuring diagnosis and follow-up of hepatitis C-positive patients. Family members suffering indirect effects of problem drug use benefit from the merger of the addiction service with general practice. The balance between the demands of the addiction service and those of general practice is maintained by holding the volume of patients using the addiction service at about 2 percent of the practice population. Tables, references