Possible indications for tonsillectomy include sleep apnea and other obstructive sleep-related breathing disorders, recurrent tonsillitis, peritonsillar abscess, periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA), and other miscellaneous rare conditions. Over the last century indications have changed, with a decrease in infectious causes and an increase in sleep apnea disorders. Sleep apnea in children is difficult to diagnose short of polysomnography (PSG) which is expensive and disturbing, especially in young children. In sleep apnea confirmed by PSG, tonsillectomy relieves the trouble in close to 80% of patients. What remains unclear is how to diagnose sleep-related breathing disorders without PSG and the efficacy of tonsillectomy in this population. Recurrent tonsillitis is generally poorly documented and randomized studies assessing the efficacy of tonsillectomy are sparse. When frequent infections are present for several years (>7 episodes/1 year, >5/2, >3/3) some benefit from tonsillectomy could be found. If fewer infectious episodes are present, the benefit of tonsillectomy is low. Peritonsillar abscess tends to be treated with quinsy tonsillectomy. Some PFAPA and psoriasis children might benefit from tonsillectomy. Tonsillectomy for other conditions is not warranted.