THE PURPOSE OF THE STUDY WAS TO EXAMINE THE FOLLOWING VARIABLES: INTRINSIC MOTIVATION (THE INMATE'S AWARENESS OF HIS NEED FOR PERSONALITY OR ATTITUDE CHANGE); EXTRINSIC MOTIVATION (THE INMATE'S PERCEPTION OF THE EXTENT TO WHICH THE SYSTEM EXPECTS HIM TO CHANGE HIS PERSONALITY THROUGH PARTICIPATION IN TREATMENT PROGRAMS); NEED (THE AMOUNT OF PERSONALITY CHANGE THE INMATE SHOULD MAKE IN ORDER TO LEAD A SUCCESSFUL LIFE); THERAPY (REGULAR ATTENDANCE AT GROUP OR INDIVIDUAL THERAPY SESSIONS); WORK (QUALITY OF PERFORMANCE ON INSTITUTIONAL JOB ASSIGNMENTS); CONDUCT (THE INMATE'S ABILITY TO FUNCTION WITHIN INSTITUTIONAL RULES); AND ADJUSTMENT (A MEASURE COMBINING WORK AND CONDUCT SCORES). STUDY SUBJECTS INCLUDED 43 INMATES WHO HAD PARTICIPATED IN THERAPY FOR AT LEAST 6 MONTHS AND 43 MATCHED CONTROLS WHO HAD NOT PARTICIPATED IN THERAPY. INMATES IN THERAPY SCORED SIGNIFICANTLY HIGHER ON BOTH INTRINSIC AND EXTRINSIC MOTIVATION VARIABLES, BUT THERE WAS NO CORRELATION WITH NEED FOR THERAPY. INMATES IN THERAPY SHOWED A MARGINALLY SIGNIFICANT IMPROVEMENT IN ADJUSTMENT, WHILE CONTROLS SHOWED A SLIGHT DIMINUTION IN ADJUSTMENT OVER THE PERIOD STUDIED. NO RELATIONSHIP WAS FOUND BETWEEN MOTIVATION AND DEGREE OF IMPROVEMENT IN ADJUSTMENT. THE FINDINGS ARE SAID TO BRING INTO QUESTION THE UTILITY OF EXTRINSIC MOTIVATION IN ENCOURAGING INMATES TO ATTEND THERAPY. SUPPORTING DATA ARE INCLUDED. (AUTHOR ABSTRACT MODIFIED--LKM)