Adenotonsillectomy (AT) is one of the most common pediatric surgical procedures performed in the United States; more than 530,000 are performed annually in children younger than 15 years of age. AT was traditionally performed for recurrent tonsillitis and its sequelae but in recent times, sleep-disordered breathing/obstructive sleep apnea in children has emerged as the primary indication for surgical removal of adenoids and tonsils. The new guidelines used by clinicians to identify children who are appropriate candidates for AT address indications based primarily on obstructive and infectious causes.