Dramatic advances in the management of erectile dysfunction have occurred over the past decade. Oral therapy with vasoactive agents has emerged as first-line treatment and has transformed both the manner in which the public views erectile dysfunction and the way health care providers deliver care. Whereas an extensive investigation was previously common in the management of erectile dysfunction, recent treatment guidelines promote a more minimalist, goal-oriented approach. In this article, we review the physiology of erection, and the pathophysiology, diagnosis and clinical management of erectile dysfunction. We also present the existing evidence for the efficacy of 3 phosphodiesterase inhibitors, the most widely used class of agents for erectile dysfunction.