The hypertension project will tailor improvement strategies to the problems identified as underlying underuse among treated but uncontrolled hypertensive patients in East and Central Harlem, New York City. Along with the communities’ 6 major health providers, we will first combine qualitative and quantitative methods to identify specific patient, provider, and system problems, and customize interventions to address them. In a randomized controlled trial, we will then randomly assign 480 patients among 4 arms: nurse management, blood pressure monitors alone, usual care, and peer led chronic disease self-management course. During the 18-month trial, patients self-monitor their blood pressure or attend a self-management course, or nurse managers will assess patients’ needs, counsel them, address any access barriers, and follow up with regular telephone contacts; convey information, including blood pressures from patients’ self-monitoring, between patients and physicians to inform possible medication changes; and ameliorate any systems problems. We will assess differences in blood pressure reductions among the 4 arms as the primary outcome, and in quality of life, patient satisfaction, costs, and cost-effectiveness as secondary outcomes. The findings will provide new knowledge about the relationship between these changes and patient and clinician knowledge, attitudes, and behaviors. The educational course is designed to teach patients tools for managing their chronic illness which will empower them to improve their overall health and is specifically tailored for patients living with asymptomatic chronic illnesses and will emphasize communication with health care providers. In partnership with community organizations and the policymakers, we will disseminate successful findings within these communities and throughout the state and the nation.