The cases of attempted suicide of 155 patients admitted to the Massachusetts General Hospital from 1944 to 1952, are reported.Some of the literature on suicide is summarized, data on the patients are compared with it, and other general findings presented.A scheme of action is evolved in an attempt to formulate the complicated reasons for suicide. Autoktonism is suggested as a word to describe the recognizable state of mind in neurotic persons about to kill themselves.Some of the ways to prevent suicide are discussed.Abstract Teaser