The relationship between knowledge and pedagogy is an important one and needs further exploration. Does a degree in archaeology provide a basis for teaching contemporary history? Is the high-flying physicist able to teach adequately the biology of a general science course? Can a primary teacher successfully work across the whole of the primary curriculum even though his or her subject expertise may lie in one or two areas? Does the phrase "the best way to learn is to teach" really underpin the teaching role? In this article the authors explore these issues and describe some of the debates and research taking place in order to suggest a reconceptualization of the field and to set out some preliminary research with preservice students. The aim is to stimulate debate around an important area, not least in providing a stronger theoretical framework against which policy and regulatory proposals can be described, analysed and critiqued.