Over the past 15 years, a growing number of mid-sized to large school district central offices have engaged in radical reforms to strengthen teaching and learning for all students districtwide. Such efforts mark a significant change in urban educational governance. The authors call these efforts "district central office transformation for teaching and learning improvement." Local governance reforms of the past typically involved the reallocation of authority between central offices and schools in a zero-sum game. By contrast, central office transformation involves strengthening the authority and attendant capacity and professional practice of both central offices and schools to strengthen teaching and learning. Central office transformation rests in part on assumptions that districtwide teaching and learning improvement is a systems challenge--one that demands the full participation of people in schools, central offices, and their local communities. Unlike efforts to restructure central offices through realigning organizational charts and adding and dissolving subunits, central office transformation involves deep institutional shifts in the nature of central office administrators' work and their relationships with schools. Particularly given the profound changes in local governance and local leadership capacity that these shifts represent, the authors view central office transformation as a major dimension of the new localism. What more specifically is central office transformation? What does the emergence of central office transformation efforts imply for a next generation of educational research? This essay takes up these issues with a review of research and recent central office transformation efforts in mid-sized to large urban district central offices. In their research review, the authors highlight that an emerging wave of research on school central offices reveals the importance of remaking the daily work of central office administrators and how central office administrators relate to schools as fundamental to teaching and learning improvement. The review underscores the promise of central office transformation as a distinct educational improvement approach. The authors also elaborate on what central office transformation involves in practice, drawing on illustrations from relatively well-developed efforts currently under way in Atlanta Public Schools, New York City Public Schools, and Oakland Unified School District (CA). The authors conclude with implications of these developments for a next generation of research on educational governance. (Contains 4 notes.)