This study aimed to examine the preservice teachers’ reflections on the contingent situations of a microteaching experience based on exploratory talk, in order to better understand preservice teachers’ emerging awareness of teaching and learning in mathematics. The findings suggest that the experience had impacted on the preservice teachers’ professional development in some ways. All the participants seemed to have valued the experience, and so may have been sensitised to work with their students in an informed way. However, some preservice teachers said that the experience had changed their beliefs in using talk as a teaching approach; and even that the experience had changed the way they wanted to teach mathematics. Others argued that the experience had raised awareness of the difficulties in working this way.