The main objective of this self-study is to reflect and document the development of our own praxis by using teacher research in our teacher education courses. By praxis we mean an ongoing interdependent process in which reflection, including theoretical analysis, enlightens action, and in turn the transformed action changes our understanding of the object of our reflection. Based on the examination of our reflective journals, collegial dialogue, and students' teacher-research reports, we have achieved three major insights: (1) Teacher Research is a vehicle of genuine praxis of teacher education; (2) Praxis involves a dialectical rationality, which is radically different from the conception of practice within an instrumental rationality; and (3) Modeling and scaffolding the praxis of teacher research for our master's students--in-service teachers--facilitate both their transformation and ours.