This investigation evaluated the effect of a peer-education program on preventing cardiovascular disease in older persons. Peer leaders at two urban senior housing residences were provided with training on cardiovascular disease and its risk factors, strategies to reduce the risk factors, and communication skills. Baseline and follow-up data were collected on residents at the two intervention and two control sites. The dependent variables were knowledge of cardiovascular disease risk factors; perceived self-efficacy to reduce calories, dietary fat and salt intake, to lose weight, to stop smoking, and to exercise regularly; and self-reported cardiovascular risk behaviors. Analysis of individual change scores between baseline and follow-up surveys showed a statistically significant increase in overall knowledge of heart disease, dietary self-efficacy, and exercise self-efficacy for the intervention group compared with the control group. This program appeared to benefit the individuals who lived in housing residences where the peer educators also resided.