Cardiovascular responses to stress reactivity has been proposed as a risk factor for hypertension. In this study, we evaluated the effects of stress reduction on both laboratory cardiovascular reactivity and ambulatory blood pressure in real life on 39 normotensive male subjects who were pretested for ambulatory blood pressure and cardiovascular reactivity to stress using a battery of laboratory stressors. Thereafter, subjects were randomly assigned to practice either the Transcendental Meditation (TM) technique or a cognitive-based stress education control (SEC) for four months. After 4 months, there was no change in cardiovascular response to stressors between the TM and control groups. However, the subjects regularly practicing TM demonstrated a significant reduction of 9 mm Hg (p < .04) in average ambulatory DBP compared to controls. Since ambulatory BP monitoring has been shown to be a better predictor of cardiovascular complications of hypertension than clinic BP, this finding may have important implications for primary prevention of CVD in normotensive subjects.