The failure of recent antihypertensive trials to document clearly a reduction in the risk of coronary heart disease (nonfatal or fatal myocardial infarction and sudden death) has important clinical implications. Although the causes of this phenomenon are unknown, it is possible that lipid and metabolic side effects of the antihypertensive drugs used in these studies negated the beneficial effects of blood pressure reduction. Angiotensin-converting enzyme (ACE) inhibitors are lipid neutral and associated with few metabolic side effects, and may be considered over agents that cause adverse effects on such parameters as serum cholesterol, glucose, potassium, and uric acid levels. ACE inhibitors are now emerging in the United States as important first-line therapy for the treatment of hypertension.