The proposed project is designed to evaluate the effectiveness of a new behavioral intervention, anger management training, for blood pressure reduction in mild essential hypertension. The focus of this treatment is on cognitive, behavioral, and physiological components of anger which have been found to be characteristic of a significant subset of hypertensives who fail to respond to relaxation training, a widely used behavioral intervention for hypertension. Moreover, anger has been identified as a contributor to hypertension and its end-organ complications. Blood pressure changes in subjects receiving anger management training will be compared with those observed in subjects receiving relaxation training and in control subjects receiving blood pressure monitoring. In the proposed study, 210 mild hypertensives who meet project criteria will be identified and randomly assigned to one of three intervention groups: anger management training, relaxation training, or waiting-list control. A comprehensive evaluation package, occurring at preintervention, at postintervention, and at post-follow-up, will include: (1) frequent measurements of resting blood pressure in the clinic and at the worksite along with 12-hour ambulatory monitoring of blood pressure at work and at home; (2) psychosocial variables including state and trait anger and anxiety, anger arousal, anger expression, assertiveness, depression, and social desirability; (3) factors which have been related to blood pressure in hypertensives including family history, diet, weight, alcohol, caffeine intake, smoking, medication, and physical activity; and (4) a protocol that includes a stress test to measure cardiovascular and catecholamine responses to laboratory challenges and a behavioral assessment of anger and hostility. After the post-follow-up evaluation, subjects in the waiting list control group will be randomly "crossed-over" into one of the two behavioral treatment groups. The primary aim of the proposed project is to examine the differential effectiveness of the two behavioral interventions--anger management training and relaxation training--in reducing blood pressure measured in a number of different settings including the clinic, worksite, and home. The most important secondary aim is to examine psychosocial and physiological characteristics to identify profiles of essential hypertensives who best respond to each of these behavioral interventions.