Functional endoscopic sinus surgery is a common adjunct to medical therapy in the management of chronic rhinosinusitis and nasal polyposis. As with most surgical procedures, there is a paucity of randomized, controlled clinical trials examining the use of functional endoscopic sinus surgery in the management of chronic rhinosinusitis and nasal polyposis. This is primarily a result of the physical and ethical conundrums faced in performing a study that involves comparing a surgical procedure with a placebo. However, there is documentation of the marked impact that chronic rhinosinusitis can have on the overall quality of life and evidence that this improves following combined surgical and medical intervention. There are many case series with large patient populations that have shown significant improvement in short- and long-term patient symptoms following surgery. These outcomes are expected to improve with even greater refinement of technology, experience, and instrumentation, and the quality of future studies may be improved by determining and using objective measures of success and, possibly, by the use of control groups.