Most professionalisation programmes to support teacher educators as research supervisors focus on the development of research skills. The methodology of practice-oriented research, in addition to a clear vision on the function, and purpose of student research often receives little attention. At the Amsterdam University of Applied Science, we developed such a vision and methodology and studied the development of 17 teacher educators as research supervisors during a programme that introduced this methodology. We questioned participants about affect, and understanding regarding their role as a student research supervisor, and their perception of their competences to perform that role. Results showed that teacher educators became more aware of their role, and became more critical about their own competencies. Growing awareness of the implications of their role as student research supervisors seemed to result in a lower self-efficacy regarding the performance of this role. Implications for the training of teacher educators are discussed.