Significant clinical and basic science advances in the field of sexual medicine have facilitated investigation of the link between endothelial dysfunction and erectile dysfunction. Most sexual medicine practitioners accept the premise that in aging men with risk factors such as increased waist circumference, diabetes, hypertension, hypogonadism, hypercholesterolemia, and insulin insensitivity, a higher prevalence of erectile dysfunction reflects systemic vasculopathy that often first presents as abnormal erectile function. Endothelial dysfunction in the pudendal, common penile, and cavernosal arterial bed can occur secondary to pelvic, perineal, or penile trauma in young men without traditional systemic vascular risk factors. Because some younger men with erectile dysfunction may have underlying vasculogenic erectile dysfunction, sexual medicine practitioners should perform sophisticated testing procedures to evaluate erectile function that can be reestablished with penile revascularization surgery.