How can I, as a teacher-researcher, read my own practice? How can I, as a teacher-researcher, theorise my practice? These are the central questions pursued in this thesis. They are pursued through three action research projects. The research took place in Firhouse Community College, a second-level school in Dublin. Each of the projects was concerned with exploring the potential of conversation in a number of different school contexts. Chapter one relates my research to the literature on action research and to the literature on dialogue in education, and relates my work to the ethical concepts of friendship and care. The chapter also outlines the methodological approach and the data used in the research. Chapter two relates the interpretative reading of my own practitioner accounts to critical theory and the emancipatory ambition of its reflective practices. A project on student friendship groups is discussed in chapters three and four. These chapters highlight friendship as an important social and educational phenomenon and identify conversation as a concomitant communicative form. These chapters theorise the concept of pedagogical conversation and relate this concept to Aristotle's theory of friendship. Chapter five gives an account of a project with a third-year English class, developed around the ideas of dialogue and friendship. In the course of the project, students organised themselves into reading and discussion groups that were largely autonomous and self-regulating. Chapter six reviews the role and place of the teacher in the discourse of the classroom, in a dialogic teaching situation, and explores the potential of dialogue as means of enquiry and reflection. Chapter seven contrasts the peaceable conversation of professional friendship with the disputatious debate that often occurs at formal staff meetings. Chapter eight offers some reflective comments on the research. This thesis lays the foundation for a theory of teaching as a form of social practice, characterised by a disposition of care that is associated with friendship, and expressed through conversation. In doing so, it makes a valuable and original contribution to the literature on teaching and school culture. In its development of a dialogic model of research, the thesis makes a contribution to the literature on action research and practitioner enquiry.