Congestive heart failure is a serious health problem in Western society. Understanding of both the basic pathophysiology and the design of rational and effective treatment of this syndrome has increased dramatically in the last ten years. However, congestive heart failure remains a highly lethal disease, which kills at a rate exceeding that of most cancers. Prevention is therefore of the utmost importance and has to come primarily from a reduction in the incidence and damage done from myocardial infarction. Improved understanding of the pathophysiology of idiopathic dilated cardiomyopathy is also needed. Through understanding of pathophysiologic principles, effective therapy based on interference with known mechanisms that are operative in the disease is now available but can be refined in the future.