Components of the program included a community education campaign, an educational intervention for private physicians, and major modifications in the process of care for hypertensives in a health care system that was the largest single provider to the target area. The intervention area was compared to a similar community in another part of the city which was served by different private and public providers. Pre- and post-intervention random samples of persons ages 18-74 were selected from each geographical area to assess the effectiveness of the program in reducing the prevalence of uncontrolled hypertension. The community intervention focused on improving awareness and need to maintain treatment. The private physician intervention focused on strategies for promoting long-term patient adherence. The public hospital clinic/systems components were: 1) educating providers, 2) instituting an evening clinic for the working poor, 3) providing tailored patient education programs which were culturally sensitive and did not require class attendance, and 4) implementing a program in the public hospital emergency center to identify and refer patients with undetected hypertension or hypertension not under regular care.