This interview sheds light on current developments threatening the disciplinary ‘heart’ of education. Taking a starting point in the continental ‘configuration’ of the field, Gert Biesta and Stefan T Siegel argue that there are forms of theory considered distinctively educational. Based on this premise, they discuss why defining educational theories (Erziehungswissenschaftliche Theorien) is so challenging, and why it is nevertheless a rewarding endeavour. By distinguishing between (genuinely) educational theories in a narrow sense and (educationally relevant) theories in a wider sense, Biesta and Siegel attempt to tackle the problem of educational theory and to stimulate the discourse on theorizing education