The etiology and pathogenesis of dilated cardiomyopathy continues to be controversial. The importance of viral and familial etiologies is becoming increasingly recognized. Molecular biology will add significantly to our understanding of these factors in the near future. The differentiation of ischemic from nonischemic dilated cardiomyopathy continues to depend on the use of coronary angiography. Endomyocardial biopsy has a relatively low yield for the detection of specific myocardial disease. To date, there is no specific treatment for dilated cardiomyopathy. Trials evaluating new inodilators have ended in disappointment. The benefits of digoxin, however, appear to be confirmed. Although there has been little progress in the prevention of sudden cardiac death in this population, signal-averaged electrocardiographic analysis shows promise as a tool for risk stratification. At present, the recommended treatment of patients with dilated cardiomyopathy remains identical to that of heart failure in general.