This study investigated differences and similarities between those inmates at the State Prison of Southern Michigan who had participated in the Academic School adult education programs and another group who had never participated in any adult education activity. Variables were personality factors as defined by the Sixteen Personality Factor Questionnaire and specified nonpersonality areas in an adult education data survey. Randomly chosen inmates were divided into 32 matched groups on the basis of items concerning age, education, recidivism, length of sentence, and participation in special groups or activities, with adult education participation or nonparticipation as the single difference. Participants were found to be significantly more rigid, undependable, and conventional than nonparticipants, who were relatively easygoing, conscientious, and imaginative. Both groups were more rigid and undependable than the general noncollege adult male population norms provided by the authors of the questionnaire. Comparisons between other groups of inmate participators and nonparticipators showed no significant differences on nonpersonality factors. Implications for student recruitment and for program planning were noted. (author/ly)