The purpose of this report is to compare the results of insulin shock therapy in a group of schizophrenic patients with the results of conservative treatment in a group of similar patients used as controls. The control group has been reported on previously.1 The criteria for diagnosis and such factors as economic, occupational and educational levels and racial composition were the same in the two groups. Likewise, the selection of the patients for admission to the hospital was identical. Thus the groups were directly comparable, and the value of insulin shock therapy can therefore be estimated. METHOD Sixty-six patients suffering from schizophrenia, in whom the disease processes were typical, were treated by means of insulin shock. This procedure was made routine; it consisted, briefly, of giving the patient progressively larger amounts of insulin until the dose was sufficient to produce coma within two or three hours after injection. The