This dissertation reports on detailed interaction research into the ways in which primary school teachers provide space for discussion during history lessons. Teachers participating in this project were asked to hold whole-class discussions on the basis of the textbook texts, instead of having their students complete written exercises individually. Productive discussions offer students the opportunity to collaboratively build understanding and enhance their individual cognitive processes. In order to realize productive discussions, teachers should facilitate interaction in which students produce longer stretches of talk and are provided the opportunity to talk and think together. Until now, recommendations to teachers holding whole-class discussions have been rather general. This thesis fulfils the need for detailed insight into teachers’ conduct during these discussions.The research shows that teachers, without having received intensive instruction, possess a large repertoire of conduct to facilitate and support discussions. For instance, the study of teachers’ ‘open and authentic questions’ revealed that one open question gives students much freedom and leads to actual discussion, while the other steers the students into a certain direction and generates only short answers. The other studies in this thesis unravel details of teacher conduct encouraging students to elaborate and to respond to each other. Apart from these nuances within specific types of conduct, this research has pointed out that teachers can facilitate and support whole-class discussions by means of less obvious conduct such as gaze, gestures and even the drinking of coffee at a moment at which the teacher would normally take a speaking turn. With the insights from this research teachers could be made more consciously competent.