The discovery of strictly medical therapies for psychiatric patients had a period of concentrated development in the 1930’s. The procedures introduced in that decade included a variety of therapeutic media: the injection of coma-producing drugs, the application of convulsion-producing electric currents, and the surgical destruction of major nerve pathways of the brain. In 1934, Meduna, a Hungarian psychiatrist, reported on the treatment of schizophrenia by the intramuscular injection of camphor in oil. Manfred Sakel, a Viennese physician, suggested in 1935 that an hypoglycemic coma might alleviate some of the symptomatology of schizophrenia. Before turning to the most recent development in the medical treatment of psychiatric illness, the tranquilizing drugs, let people consider some of the common features of these discoveries of the 1930’s. Patients to be exposed to the experimental procedure were selected carefully and in accordance with general principles of medical conservatism.