Entitled “The role of teachers in mathematical reasoning in the classroom: an interpretative perspective”, her lecture on 5 March will address the question of how teachers' actions frame mathematical reasoning processes in the classroom. From the perspective of interpretative classroom research, she reconstructs what (supportive) actions by teachers look like in everyday classroom practice. In doing so, she highlights that these actions can have a constructive effect on mathematical reasoning processes, but can also be “disruptive” and thus potentially hinder the development of sound and productive mathematical reasoning.