Sympathetic nervous system activation plays an important role in the genesis of symptoms, functional impairment, progressive ventricular dysfunction, and mortality in patients with heart failure. Prospective, randomized clinical trials of beta-blockers in patients with heart failure have demonstrated mortality reductions in patients across the spectrum of clinical presentations and etiologies. Additionally, these trials have provided important information regarding the indications, dosing, and extent of therapeutic benefits of the different beta-blockers studied in patients with heart failure. The recognition that beta-blockers relieve symptoms, reduce hospitalizations, and prolong survival in patients with heart failure represents one of the most important therapeutic advances in the treatment of this complex disorder. Beta-blockers, along with angiotensin-converting enzyme inhibitors and aldosterone antagonists, now represent the standard of care for patients with heart failure.