Obstructive sleep apnea syndrome is an increasingly common disorder, but the etiology and site of obstruction often remain unknown. The obstruction seldom is imaged or identified. All surgical procedures must be directed toward the anatomic site of obstruction. Currently, it is very difficult to identify the site of obstruction in the awake, nonsupine patient. Therefore, better diagnostic methods must be developed to help direct treatment options and improve surgical outcomes. This article will help surgeons identify possible sites of obstruction and direct surgical intervention.