Despite improved understanding of both disease mechanisms and the quality of care, congestive heart failure (CHF) remains a serious clinical problem. The traditional treatments, diuretics and digitalis, continue to play a major role in the management of many patients with CHF; however, in the last decade, angiotensin-converting enzyme (ACE) inhibitors have been added as an important treatment option. These agents counteract the overstimulation effects of diuretics on the renin-angiotensin-aldosterone system. In addition, some studies indicate that ACE inhibitors may improve symptoms and survival. Recent evidence suggests that in patients with mild to moderate CHF, ACE inhibitor and a diuretic should be administered with or without digitalis to achieve the maximum clinical benefit.