Histories of twentieth-century surgery have focused on surgical ‘firsts’ – dramatic tales of revolutionary procedures. The history of tonsillectomy is less glamorous, but more widespread, representing the experience and understanding of medicine for hundreds of children, parents and surgeons daily. At the start of the twentieth century, tonsillectomy was routine – performed on at least 80 000 schoolchildren each year in Britain. However, by the 1980s, public and professional discourse condemned the operation as a ‘dangerous fad’. This profound shift in the medical, political and social position of tonsillectomy rested upon several factors: changes in the organisation of medical institutions and national health care; changes in medical technologies and the criteria by which they are judged; the political, cultural and economic context of Britain; and the social role of the patient. Tonsillectomy was not a mere passive subject of external influences, but became a potent concept in medical, political, and social discourse. Therefore, it reciprocally influenced these discourses and subsequently the development of twentieth-century British medicine. These complex interactions between ‘medical’ and ‘non-medical’ spheres question the possibility of demarcating what is internal from what is external to medicine.