The statistical report of 172 Great Books groups is based on one of a series of studies of participants, leaders, and educational effectiveness of study discussion programs sponsored by the Fund for Adult Education. During 1957, interviewers administered questionnaires to 1909 participants in "primary sampling units." It was found that participants tended to be well educated, of high status, socially active, and young. A combination of social and intellectual motivations were attributed to participation. Great satisfaction was expressed, since dissatisfied persons dropped out of the program. The strongest effect of continued participation was an increased knowledge of the liberal arts and humanities, while members also became broader-minded religiously and politically. There was no effect in esthetic areas nor in serious reading outside the program. Greater interest was expressed in national and world affairs than in the community, but the latter tended to increase with participation in the Great Books program. Participants were active in community organizations and programs to change or improve the community. A supplemental report, included in the appendix, reports on studies of dropouts and retention among individuals of varying characteristics. A list of Great Books readings and the questionnaire are also included in the appendix. (pt)