After completing his PhD dissertation on John Dewey's theory of inquiry at Harvard's philosophy department in 1954, Donald A Schon produced a prolific number ofpublications in a wide range of disciplines, having edited, authored or co-authored several books and over 160 articles (Newman, 1999). He considered himself a 'transplanted philosopher' (Newman, 1999: 10). As he was the Ford Professor of Urban Studies and Education in the Department of Urban Studies and Planning at the Massachusetts Institute of Technology from 1972 until his death in 1997, others would consider him an cducator. Although he obviously was involved in many adult education programmes and research efforts over his 43-year career, he certainly would not have considered himself to be, or perceived to be, an adult educator. So why does Donald Schon merit a chapter in a book on Thinkers in Adult and Continuing Education? This chapter will show that Donald Schon has indeed been a major influence on the field of adult and continuing education in the 1980s and 1990s, through his two books on the reflective practitioner. Although he published two later books on this same theme (Schon, 1991; Schon and Rein, 1994), his initial presentation in The Rejlective Practitioner: How professionals think in action (1983) and Educating the Rejlective Practitioner: Toward a new design Jor teaching and learning in the professions (1987) was the foundation ofhis influence.