The volume of literature attesting to the clinical benefits of exercise training in patients with stable chronic heart failure (CHF) is substantial. Training can improve symptoms and exercise capacity, as well as reducing morbidity, mortality, and rates of emergency hospitalization. These benefits are apparent in all patients with stable CHF, irrespective of age or sex, or the etiology or severity of heart failure. Training regimens for patients with stable, systolic CHF should form part of a comprehensive heart-failure support effort and are best delivered using supervised in-hospital exercise combined with some training at home or in a group setting in community centers. In this Review, the modes and intensity of exercise training, selection of patients, duration of training effects, and other clinical guidance for using this treatment option are discussed.