The sympathetic nervous system, when activated, can increase blood pressure, affect lipid and glucose metabolism, promote cardiac hypertrophy, and amplify the cardiovascular responses to cigarette smoking. These observations suggest that an activation of the sympathetic nervous system may be one of the important pathophysiologic links among the development of hypertension, dyslipidemia, glucose intolerance, insulin resistance, cardiac hypertrophy, and the adverse effects of cigarette smoking. The enhanced adrenergic activity and the end-organ responses are determined by genetic predisposition and environmental and behavioral factors. The impact of pharmacologic therapy must be considered in selecting antihypertensive drugs. If the hypothesis of a “sympathetic link” proves to be correct, then an ideal agent would be an effective inhibitor of the adrenergic nervous system.