Tonsillectomy has been performed since at least the time of Celsus' who was born in 25 B.C. In the last century tonsillectomy and adenoidectomy have come to be among the world's most frequent operations, yet the indications, particularly for tonsillectomy, are still far from standardized, especially recurrent acute sore throats the most common problem. Because our knowledge of the functions of the lymphoid tissue of Waldeyer's ring, and of its diseases, is still scanty, our knowledge of how and when to modify these diseases is in its infancy.Adenoidectomy and tonsillectomy should be regarded as two separate operations, each with their own indications; when adenoidectomy is performed, the tonsils should not be removed unless they too are judged to be contributing to the patient's ill health. There is also some measure of agreement on the indications for adenoidectomy, which include recurrent acute suppurative otitis media, recurrent secretory otitis media, chronic otitis media, recurrent rhinitis and sinusitis, and persistent nasal obstruction. But in the few controlled trials comparing operated with non-operated children, the findings concerning the otologic outcome were inc~nsistent.~-~ The design of these trials has been criticized on the grounds that children 'urgently' in need of operation were withdrawn on ethical grounds, thus confining the trials to patients nearer the borderline for surgery; criticisms were also made on other grounds including observer bias6-' Nevertheless most otologists agree that adenoids often do predispose to ear disease and that total adenoidectomy will abolish or diminish the attacks. However, there are some patients whose ear disease is not improved by adenoidectomy. Radiographic studies of Eustachian tube function using a contrast medium have shown that a few patients have considerable retrograde reflux from the nasopharynx into the middle ear with each swallow, and these patients were found to have the same or worse ear disease after aden~idectomy.~ Studies of middle ear and nasopharyngeal pressures have also been donel' in a further attempt to aid selection for adenoidectomy but the results are not yet conclusive. These tests are not simple enough for clinical use, but as research tools have cast some interesting light on possible causes of failure. Large prospective studies of the otologic outcome of adenoidectomy, including correlation with the results of these investigations, are required.The indications for tonsillectomy are less clear-cut, and agreement is greatest only for the rarer indications such as peritonsillar abscess, and extreme obstruction, which it is now realized can give severe complications such as cor pulmonale.6 The main problem arises in children and adults with recurrent acute sore throats-patients with whom the otolaryngologist is confronted daily. There is a regrettable lack of exact criteria, both for and against 4