Although heart failure is common, disabling, and deadly, there are now many effective treatments, at least for patients with low left-ventricular ejection fraction. For all, angiotensin-converting-enzyme inhibitors and beta blockers are the essential disease-modifying treatments, improving symptoms, reducing hospital admissions, and increasing survival. Implantable cardioverter defibrillators also improve survival. For patients with persistent symptoms, angiotensin-receptor blockers and aldosterone antagonists have additional benefits. These treatments are now preferred to digoxin, although this drug can still be useful at an earlier stage in patients with atrial fibrillation. In some patients with persistently severe symptoms and a wide QRS on the electrocardiogram, cardiac resynchronisation therapy also reduces mortality and morbidity. The role of other markers of ventricular dys-synchrony is under investigation. There is growing evidence that left-ventricular assist devices are indicated in some patients with end-stage heart failure. Organised delivery of care also improves outcome. However, there is still no firmly evidence-based treatment for heart failure with preserved ejection fraction. Many new pharmacological, device, and surgical treatments for heart failure are currently under evaluation in clinical trials, and other approaches, including stem-cell treatment, are at an earlier stage of investigation.