Sexual function is one element of QOL that may be significantly altered following treatment for rectal cancer, but the incidence and contributing risk factors are generally poorly understood. Nevertheless, the impact of rectal cancer therapy on sexual function should be conveyed to patients preoperatively. In addition to helping patients evolve realistic expectations, it will help clinicians identify those for whom interventions may be appropriate. In the past 10 years, there has been an increase in the number of studies reporting sexual dysfunction following rectal cancer treatment. However, these studies are difficult to interpret collectively for a variety of reasons. Most importantly, sexual dysfunction lacks a standardized definition, which leads to poor comparability between studies. The best inclusive definitions describe sexual dysfunction as a collection of distinct symptoms, which differ for men and women. The absence of sexual activity is sometimes used as a surrogate for sexual dysfunction, but this is confounded by an individual's desire and opportunity for sexual activity, and may not be an accurate reflection of physiologic functionality. Additional factors complicating assimilation of studies include the absence of baseline data, missing data, small sample sizes, and heterogeneity in use of validated and nonvalidated instruments. The purpose of this article is to systematically review the contemporary literature reporting sexual function after rectal surgery to determine the overall risk of sexual dysfunction, evaluate possible contributing factors, and identify questions that should be addressed in future studies.