Suicide occurs in a great variety of settings, and to the psychiatrist who deals with personality disorders daily it is a serious practical problem. The generally accepted principle that all depressions are potentially suicidal is a simplification that has little value unless it is associated with a deeper analysis of the patient's life situation. The underlying factors are individual but, complex as these may be, it is reasonable to assume that some common determinants exist in such a universal phenomenon. Study of persons suffering from mental disease should help in this evaluation. The present discussion consists of a general review of the clinical records of one hundred patients who have committed suicide. The group comprises sixty-one men and thirty-nine women. The study includes a diagnostic enumeration, a correlation of the intensity of the desire for suicide with the type of psychosis, some reference to the methods used and an analysis