The extent, nature, and development of critical reflection was examined in three secondary social studies preservice teachers over the course of one semester of student teaching. Using an action research case study methodology, the researcher looked for evidence of the study participants’ deliberation about the ethical and moral basis of their work as teachers, and reflection on the broader social conditions of schooling. The study revealed limited, but significant, evidence of critical reflection and critically reflective teaching. Factors of influence are also discussed. The results lend support to the view that critical reflection can be a practical aim of preservice teacher education.