The central question of this study was: What are the contributions in theory and practice Malcolm S. Knowles has made to the emerging field of adult education? The nature of the study as contemporary history of a living person's educational work, required the findings to be preliminary. The source of information used to answer the central question were: interviews with and questionnaire responses of contemporaries of Knowles and Malcolm S. Knowles who served as "prime information resource;" writing so Knowles and others; and documents and proceedings of a variety of organizations influenced by Knowles. Sections were included on the influence that shaped him as an adult educator; his administrative role at Chicago Central YMCA and Adult Education Association of the U.S.A; his being professor of Education at Boston University; and his spin-off influence on total social systems and individuals, in addition to numerous students and graduates. His influence on more than forty social systems are described and his influence on forty-four individuals is described. George F. Aker's model of twenty-three essential adult educator behaviors was the tool used to determine areas of strength and weakness of Knowles as asserted by others. Three conclusions concerning Knowles seem warranted: (1) Only the activities and vocation which offered him the opportunity to pioneer and do what he perceived as socially useful could ultimately capture his efforts - adult education thus far has set this test; (2) Eduard C. Lindeman's book "The Meaning of Adult Education" formed the central overall perspective, inspiration, influence and foundation for Knowles' contribution to the field of adult education; and (3) Knowles' social science research base in his adult education contributions stem from Alvin Johnson and his book "The Clock of History."