This paper begins by contrasting Schon’s ‘epistemology of practice’ with Bernstein’s three fold distinction between singulars, regions and fields of practice as ways of conceptualizing professional knowledge. Both of address the theory/practice issue that lies at the heart of the problems facing all professions; however it is Schon’s concept of ‘reflective practitioner’ that dominates the field of professional development. The paper will indicate the potential of Bernstein’s conceptualization with reference to the problems of designing professional curricula for future teachers on specialist vocational programmes.