THE SUBJECT POPULATION CONSISTED OF A REPRESENTATIVE SAMPLE OF THOSE MALE INMATES WHO HAD BEEN INCARCERATED AT THE STILLWATER STATE PRISON AND ST. CLOUD REFORMATORY, AND THOSE INMATES TRANSFERRED FROM EACH INSTITUTION TO THE ST. PETER SECURITY HOSPITAL FOR THE CRIMINALLY INSANE BETWEEN 1959 AND 1974. FIFTY SUBJECTS WERE CHOSEN ON A RANDOM BASIS FOR EACH OF THE FOLLOWING YEARS: 1959 1964, 1966, 1968, 1970, 1972, AND 1974. THOSE INMATES WHO HAD BEEN TRANSFERRED FROM EITHER THE PRISON OR REFORMATORY TO ST. PETER SECURITY HOSPITAL DURING THE YEARS 1959, AND 1964 THROUGH 1974 WERE ALSO EXAMINED AS A COHORT, COMPARISON GROUP FOR THE GENERAL PRISON POPULATIONS AT THE TWO CORRECTIONAL FACILITIES. IN ADDITION, TWO SUBGROUPS WITHIN THE PRISON POPULATION WERE EVALUATED SEPARATELY IN RESPECT TO CERTAIN RELEVANT VARIABLES. THE SUBGROUPS WERE: (1) THOSE 23 INMATES AND INMATE PATIENTS WHO SUICIDED OR DIED 'EQUIVOCAL' DEATHS AT EACH OF THE THREE FACILITIES INVOLVED IN THE STUDY; AND (2) THOSE INMATES WHO HAD ACTUALLY ATTEMPTED SUICIDE OR EXHIBITED SUICIDAL BEHAVIOR OR IDEATION AT EITHER THE STATE PRISON OR STATE REFORMATORY DURING THE YEARS 1973 AND 1974. EQUIVALENT DEMOGRAPHIC, DESCRIPTIVE INFORMATION, AND SOCIOLOGICAL VARIABLES, IN ADDITION TO MINNESOTA MULTIPHASIC INVENTORY AND INTELLIGENCE QUOTIENT RESULTS, WERE COLLECTED, SUMMARIZED, AND ANALYZED FOR THE GENERAL PRISON POPULATION AND THE TWO SUBGROUPS. THE INMATE POPULATIONS INCARCERATED IN THOSE YEARS IN THE LATTER PART OF THE PERIOD STUDIED REVEALED TENDENCIES TO HAVE LESS SATISFACTORY ADJUSTMENT POTENTIAL THAN INMATES FROM PREVIOUS YEARS. IT IS BELIEVED THAT BECAUSE THESE POPULATIONS ARE YOUNGER, LESS INVOLVED WITH SOLID OR PERMANENT RELATIONSHIPS (RELIGIOUS AFFILIATION AND MARITAL STATUS), WITH INCREASED LEVELS OF ANXIETY AND MALADJUSTED THINKING, AND EXHIBIT POORER ADJUSTMENT POTENTIAL, THEY WERE SOMEWHAT MORE LETHAL AND VOLATILE THAN PRISON POPULATIONS FROM EARLIER YEARS. THERE IS THEREFORE AN INCREASED LIKELIHOOD OF SELF-DESTRUCTIVE BEHAVIOR. THE APPENDIX INCLUDES STUDY DATA, AND A BIBLIOGRAPHY IS ALSO PROVIDED. (RCB)