How teacher development can be fostered has always been a primary concern within educational research. While researchers have repeatedly emphasized the use of dialogue as a useful means of fostering learning, little detailed investigation has been conducted to explicate the role of dialogic reflection in teacher learning and how it can be incorporated into a professional programme to ensure the programme's effectiveness from the teacher's perspective. Accordingly, this paper reports the results of a qualitative study examining, based on teachers' perceptions, the role of dialogic reflection in fostering professional development and the essential determinants contributing to its effective implementation, in an Asian context. Based on the analysis of in-depth semi-structured interviews and reflective journal entries collected from four secondary school English language teachers engaged in a programme promoting professional growth through dialogic reflection, the study's findings revealed that dialogic reflection was considered useful in facilitating collective scaffolding among teachers. More important, eleven factors that support teacher development through dialogic reflection, focusing on four major areas--multiple pathways to quality reflection, teachers' dialogic qualities, conditions conducive to dialogic reflection, and kinds of institutional support--were identified. Implications for teacher development and suggestions on future research are discussed.