In the United States, 8 million adults have peripheral artery disease (PAD), a number that is likely to escalate as the population ages.1,–,3 Lower-extremity PAD is a component of systemic atherosclerosis and confers a markedly heightened risk of cardiovascular morbidity and mortality.4,–,7 It is now established that PAD accelerates functional decline leading to physical disability.8,9 Exercise therapy combined with comprehensive secondary prevention has the potential to benefit patients with PAD by preserving or improving functional capacity and reducing cardiovascular events. Accordingly, this review will address the relation between exercise intolerance and outcomes in patients with PAD; the effects of exercise training in PAD and the many possible mechanisms of benefit; and the potential role of comprehensive secondary prevention programs in these patients.