This detailed revision of the text first published in 1941 is chiefly the work of Mittelmann. The authors state that they are attempting to present an integrated picture of the psychologically disturbed individual, utilizing genetic, clinical, experimental, psycho-analytical, psycho-biological, comparative, sociological, and anthropological observations. As a single introductory text for medical students, psychological students, sociological students and perhaps also for senior nurses it is doubtful if a better is available. The student is referred to further reading and the list, both of monographs and articles, is up to date (one thousand titles).