This will be a prospective cohort study examining subjects between the ages of 2 and 18 who are having AT for treatment of obstructive sleep apnea (OSA) and are considered high risk for residual OSA after surgery. High risk will be defined based on the following criteria: obesity, Down syndrome, African American race, severe baseline OSA, and age > 7 yrs. Eligible subjects will be recruited from the pediatric otolaryngology clinic at the time of initial evaluation for AT. Subjects will undergo a sleep endoscopy under moderate sedation at the time of AT. All patients will be asked to complete a preoperative sleep study to confirm the diagnosis of OSA and a postoperative sleep study to determine the impact of AT and the presence of residual OSA. Secondary outcome measures will include several questionnaires assessing generic and OSA-specific quality of life as well as subjective measures of cognitive/executive functioning and daytime sleepiness.