Grounded in the frameworks of action research, Critical Friends Groups (CFGs), and reflective practice, this article presents an overarching action research study connected by individual action research studies to explore what a cohort of preservice elementary Master of Arts in Teaching (MAT) candidates learned from the process of teacher action research as a (re)imagined form of authentic professional development to aid with student achievement in urban settings. Data came from a cohort of 12 urban preservice teachers' written reflections on their processes of conducting a four-month Teacher Research Project (TRP) during their student teaching semester in Spring 2016. Teachers' voices are prominent in this study. All candidates noted how important the TRP was to their own professional development as it was an authentic experience unlike any form of professional development they had previously experienced. Data analysis reveals that their conceptions within professional development were further disaggregated into five sub-themes: individual, student, community network, pedagogy, and empowerment. Implications for preservice teacher education and inservice professional development are discussed.