THE ANALYSIS DRAWS ON DATA FROM INTERVIEWS WITH 333 MEN WHO HAD INJURED THEMSELVES (ATTEMPTED SUICIDE) WHILE CONFINED AND 77 WHO HAD NOT. IN ADDITION, THE CHARACTERISTICS OF 772 INMATES WITH HISTORIES OF SELF-DESTRUCTIVE BEHAVIOR ARE COMPARED WITH THOSE OF A RANDOM SAMPLE (1,525) FROM THE GENERAL INMATE POPULATION. THE ANALYSIS SHOWS THAT PRISON AND JAIL PRESENT DIFFERENT TYPES OF PROBLEMS TO INMATES AND DIFFER IN THE EXTENT OF EMOTIONAL SUPPORT REQUIRED BY INMATES. THE JAIL ENVIRONMENT IS A DISORGANIZING, ANXIETY-PRODUCING ONE IN WHICH SUPPORT FROM THE INMATE'S FAMILY CAN BE A CRUCIAL COPING RESOURCE. PRISON IS MORE OF A DANGEROUS WORLD, WHERE MAINTENANCE OF A MANLY IMAGE IS IMPORTANT FOR EFFECTIVE COPING. COMPARATIVELY INEXPERIENCED, NONVIOLENT, YOUNG PRISON INMATES ARE MORE LIKELY TO INJURE THEMSELVES THAN ARE MORE SEASONED INMATES. THE STATISTICAL PICTURE IS LESS CLEAR FOR JAIL INMATES. IT APPEARS THAT PERSONAL CHARACTERISTICS ARE LESS CAPABLE OF DISCRIMINATING BETWEEN MEN WHO INJURE THEMSELVES AND OTHER INMATES IN JAIL THAN PRISON. FEAR WAS THE DOMINANT THEME IN INTERVIEWS WITH SELF-DESTRUCTIVE PRISON INMATES, WHEREAS SUPPORT WAS A MORE COMMON THEME FOR SELF-DESTRUCTIVE JAIL INMATES. STRATEGIES FOR REDUCING THE STRESSES OF JAIL CONFINEMENT ARE CONSIDERED, TOGETHER WITH CRISIS INTERVENTION TECHNIQUES THAT ADDRESS THE PROBLEMS OF SELF-DESTRUCTIVE JAIL INMATES. SUPPORTING DATA, A LIST OF REFERENCES, AND A REVIEW OF RELATED STUDIES ARE INCLUDED.