Conventional professional development, while still in full swing in many places, has been widely maligned for its passive approach to learning, its failure to address local differences, and its often single-event format. While the corrective move to more collaborative models of professional learning has been heralded, few empirical studies to date have demonstrated impact on classroom practice or student learning outcomes. What is missing in both approaches, we argue, is a focus on pedagogy that guides teachers' efforts at improvement. To address this absence, we elaborate our "reassembled" approach to professional development, Quality Teaching Rounds. We argue that bringing together approaches to teacher development that privilege collaboration, community, and context with a substantive pedagogical framework will deliver more powerful professional development that makes a substantial impact on practice and produces measurable effects.