Autonomic arousal is produced by both physical and psychological stresses. Exposure to physical stress in the form of exercise is beneficial for hypertension and coronary heart disease, while repeated exposure to psychological stress is harmful. The cardiovascular response produced in an individual on exposure to psychological stress is modulated by the psychological susceptibility of the individual, which, in turn, is influenced by the individual’s personality and environment. Obesity, diabetes mellitus, and genetic predisposition are risk factors for the development of essential hypertension. Since hypertension is becoming more prevalent in the rapidly developing areas of the world including India, much research is being conducted to diagnose and treat those affected by this disease, as well as to identify the individuals who are at risk of developing future hypertension.