This article discusses the problems posed for an adequate understanding of the multiple inputs into knowledge by the continuing epistemological dominance of scientific knowledge. This dominance is matched by the institutional dominance of academics in relation to practitioners. Practitioner knowledge is to be seen as part of the wider activity of social problem solving, which we would undertake more intelligently if we were able to identify and value the non-scientific knowledge inputs on which it depends as much as on the input of science. The article sees a more inclusive and ‘non-scientistic’ map of knowledge as the central condition for developing genuine partnership and exchange between academics, practitioners, and ordinary knowers. Action research is located as a valuable contribution which science can make to the improvement of practice, but it is not accepted as adequately taking up the non-scientific knowledge components of practice in particular, and social problem solving in general.