AbstractBetween 1892 and 1947, American institutional superintendents argued three distinct, though overlapping, cases for sterilizing mentally retarded people: sterilization to maintain institutional order, sterilization for eugenic control, and sterilization for controlling the growth of institutional populations. Departing from recent critics who see sterilization as a debate between 'segregation or sterilization’ and who link this debate principally to the eugenics movement, I argue that superintendents drew on the above rationales to preserve their institutions in the face of several external factors, not merely eugenics. As such, sterilization became a ‘medical’ procedure constructed not so much for its explicit purpose ‐ stopping procreation, but to maintain institutional stability and preserve professional prer