Professionalisation in teaching has been the topic of extensive research in recent years, following in general two different approaches: the "competence-based approach" and the "critical reflection approach". With large-scale comparative studies such as PISA, TIMMS and PIRLS at the beginning of the 21st century, the former approach came to dominate the field and--especially in Germany--a specific model of professionalisation advanced to the status of a paradigm. However, this model does not seem unproblematic when one considers its roots. In this article I begin by inquiring into the concept and methodology behind the status quo in order to reveal its limitations. As a means of developing this concept further, I then introduce a model of educational expertise that takes as its theoretical foundation the didactic triangle, which has a rigid systematic structure for critical and reflective thinking about teaching and is backed up by empirical findings. At the core of this model of educational expertise are "mind frames," a concept established by John Hattie. They may be seen as a theoretically founded and systematically structured interaction between competencies and attitudes backed up by empirical findings. Thus, they stand for an integrative model for professionalisation in teaching. Finally, I use this model to provide an outlook on university teacher education.