Intensive examination of cases of patients with respiratory and cardiac disease who committed suicide while in Veterans Administration General Medical and Surgical Hospitals, and of control cases matched in diagnosis, severity of illness, age, religion, and other factors, revealed a number of personality and behavior items which significantly differentiated between them. In general, the suicides seemed more emotionally disturbed, had poorer relationships with hospital staff and family, and were seen as "problem" patients because of their provoking, complaining, and demanding behavior. One major pattern of behavior emerged which was tentatively named the "dependent-dissatisfied" pattern. A number of suggestions are offered for prevention.