This paper is concerned with teaching and learning in a blended e-learning course that supports students in reflecting on and transforming their practice. In this paper we focus on two key aspects of the online learning environment: (i) the selection of the topic of discussion (the discussion question) by the tutor and how this influences the quality of the discussion; (ii) the interventions of the tutor within the online discussion. The aim is to understand why some online discussions "take off" in terms of numbers of postings and quality of engagement whilst others are less successful. Our findings show that the nature of the question impacts on discussion outcomes and that it is therefore important for tutors to pose a range of different types of questions to students in line with learning objectives. If the tutor structures discussion and chooses questions carefully there may be less need to intervene to stimulate discussion or keep it on track than is sometimes assumed. This shifts the role of the tutor somewhat toward more preparatory and plenary work with less tutor participation required to support the development of discussion skills amongst students, particularly during later stages of the course. (Contains 8 figures.)