For some teachers, the call for more dialogic instruction and less monologic instruction has led to the belief that student-led discussions require complete teacher silence. That leads to questions about whether there is enough scaffolding for the students when the teacher does not speak; on the other hand, a teacher-centred classroom invokes the same questions. In this study, we examined whole-class discussions led by two high school English teachers. We found that student-led dialogues do not automatically result in greater disciplinary depth and that teacher-engagement does not necessarily foster student passivity. Rather than thinking about discussions on either extreme, we advocate a balanced approach in which all voices in the classroom are valued.