Heart failure (HF) occurs when the heart is unable to eject enough blood from its chambers into the circulation to satisfy the needs of the body. The heart consumes more energy per gram than any other organ. Heart failure has reached epidemic proportions worldwide. There is much talk and writings regarding failures to prevent recurrent HF (rehospitalization) by experts who do not advise using digoxin, and diuretics are used inappropriately. The specific treatment of HF requires sound and up- to-date knowledge of the pathophysiology of HF, and the actions, indications and side effects of the pharmacological agents used in its management. This chapter covers the patient assessment, factors precipitating heart failure, causes of heart failure, selective physical examination, diagnostic testing, management, and cardiac resynchronization therapy.