Depression in primary care is a chronic disease. As with most chronic diseases, long-term adherence to treatment plans is problematic. Evidence-based systems of care address this problem, but persistence and dissemination of systems after testing is a new problem. The three-component model for the care of patients with depression is a system of widely applicable, easily transported strategies and materials to address dissemination. The three-component model provides a series of routines (processes for structured diagnostic and follow-up-care with a time line) and division of responsibility, including a role for a telephone care manager. In the three-component model, clinician and office education create a prepared practice that is predisposed to providing evidence-based depression management. Enabling elements include the telephone care managers, who are trained to promote adherence to a management plan, and a supervising psychiatrist. The key reinforcing element is care manager reports about patient response to treatment. The three-component model is bound together by a common depression diagnostic and severity measure that facilitates communication and treatment decisions.