In this article I explore the concept of theories-in-use within a qualitative research study to analyse the role of reflection in bringing about change in practice in the professional development of 18 primary school teachers. Cyprus provides the context for the study. The restrictions on professional development in Cyprus, through the state-managed structure of career progression and the limited opportunities for teacher development within the formal controlling structure of the Ministry of Education and Culture (MOEC), provide an interesting opportunity to explore the potential of reflection as a self-help device. The findings of the study reveal the kinds of professional exchange in which the teachers engage and show how theories-in-use can both limit and promote the critical examination of practice. They also reveal how length of service impacts on the ability to change one's own practice. The article concludes with a discussion of implications for the findings for Cypriot teachers' professional development. (Contains 4 tables and 1 figure.)