The Hypertension Detection and Follow-up Program (HDFP), in a community-based, randomized controlled trial involving 10,940 persons with high blood pressure (BP), compared the effects on five-year mortality of a systematic antihypertensive treatment program (Stepped Care [SC]) and referral to community medical therapy (Referred Care [RC]). Participants, recruited by population-based screening of 158,906 people aged 30 to 69 years in 14 communities througout the United States, were randomly assigned to SC or RC groups within each center and by entry diastolic blood pressure (DBP) (90 to 104, 105 to 114, and 115 + mm Hg). Over the five years of the study, more than two thirds of the SC participants continued to receive medication, and more than 50% achieved BP levels within the normotensive range, at or below the HDFP goal for DBP. Controls of BP was consistently better for the SC than for the RC group. Five-year mortality from all causes was 17% lower for the SC group compared to the RC group (6.4 vs 7.7 per 100, P less than .01) and 20% lower for the SC subgroup with entry DBP of 90 to 104 mm Hg compared to the corresponding RC subgroup (5.9 vs 7.4 per 100, P less than .01). These findings of the HDFP indicate that the systematic effective management of hypertension has a great potential for reducing mortality for the large numbers of people with high BP in the population, including those with "mild" hypertension.