BACKGROUND Peer-led interventions to improve chronic disease self-management can improve health outcomes but are not widely used. Therefore, we tested a peer-led hypertension self-management intervention delivered at regular meetings of community veterans' organizations. METHODS We randomized 58 organizational units ("posts") of veterans' organizations in southeast Wisconsin to peer-led vs. professionally delivered self-management education. Volunteer peer leaders at peer-led posts delivered monthly presentations regarding hypertension self-management during regular post meetings. Volunteer post representatives at seminar posts encouraged post members to attend 3 didactic seminars delivered by health professionals at a time separate from the post meeting. Volunteers in both groups encouraged members to self-monitor using blood pressure cuffs, weight scales, and pedometers. Our primary outcome was change in systolic blood pressure (SBP) at 12 months. RESULTS We measured SBP in 404 participants at baseline and in 379 participants at 12 months. SBP decreased significantly (4.4mm Hg; P < 0.0001) overall; the decrease was similar in peer-led and seminar posts (3.5mm Hg vs. 5.4mm Hg; P = 0.24). Among participants with uncontrolled BP at baseline, SBP decreased by 10.1mm Hg from baseline to 12 months but was again similar in the 2 groups. This pattern was also seen at 6 months and with diastolic blood pressure. CONCLUSIONS Our peer-led educational intervention was not more effective than didactic seminars for SBP control. Although peer-led educational programs have had important impacts in a number of studies, we did not find our intervention superior to a similar intervention delivered by healthcare professionals. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov NCT00571038.