Drug-induced sleep endoscopy (DISE) is an upper airway evaluation technique in which fiberoptic examination is performed under conditions of unconscious sedation. Unique information obtained from this 3-dimensional examination of the airway potentially provides additive benefits to other evaluation methods to guide treatment selection. This article presents recommendations regarding DISE technique and the VOTE Classification system for reporting DISE findings and reviews the evidence concerning DISE test characteristics and the association between DISE findings and treatment outcomes.