This is a study of one hospital working out for itself answers to questions raised by the use of insulin-shock in schizophrenia.At the Pennsylvania Hospital there have been immediate and important gains in one-half of all patients, and in two-thirds of acute cases (less than 18 months in duration).After two years these gains remained in only one-fourth of all patients, but in one-half of the acute cases.Control cases in the same hospital were found to show similar gains, two years from the time of admission, in one-sixth of all cases. These gains were without important relation to the previous duration of illness.The experience of one hospital indicates that insulin-shock is a strikingly effective agent in schizophrenia. It also indicates a need for supportive measures to hold more firmly the gains that come quickly but which often tend to disappear.Abstract Teaser