In recent years the scope of various physical psychiatric treatments has been defined more clearly. Broadly speaking, continuous sleep for acute and subacute anxiety reactions, electro-convulsive treatment for depressions, insulin comas for schizophrenia with or without fits, malaria for G.P.I., and so on. In 1941 my colleagues, Drs. Sargant and Craske, described a modification of insulin shock therapy for treatment of war neuroses in the Services. In 1944 we find the method maintaining its effectiveness, its indications more definite, its scope widened through trial in various psychiatric states, and checked by control experiments. From the 850 odd patients so treated at Sutton I have selected some 320 as the basis of this paper, whose courses of insulin I have given personally. The great majority of this number are civilians, and the forms of their illnesses do not differ materially from those familiar in peace time. In properly chosen cases the results are as satisfactory as with Service personnel. The treatment is free from the potential dangers of other physical methods.