This paper sets out to examine the place of theory in preschool education, considering the theories to which practitioners and providers have access and which provide a rationale for everyday practices and shape the experiences of young children. The paper reflects the circumstances of preschool provision, practices and thinking in the UK in general and in Scotland in particular. The central argument is that while there may be little obvious recourse to theorising and limited exposure to explicit theory about children’s (...) development, learning and education, practitioners and those responsible for provision have tacit understandings or implicit theories which can be seen to shape their practices. The paper begins by considering the explicit theory which practitioners are exposed to through the development of practice guidance and professional education. This is followed by an examination of the explicit theories adopted from psychology and more recent theoretical developments which have their roots in other disciplines and perspectives. Some influences on practitioners’ implicit theories are discussed before considering two key aspects of the dominate consensus about good practice: that play is the medium through which children learn and that practice should be child-centred. The paper concludes with a discussion of the ‘identity’ of preschool education theory and the benefits of articulating the implicit theory and folk beliefs on which local practices are based. (shrink)