This paper examines how urban school districts that have substantially improved student performance emphasize improvement of education guided by rigorous standards for teachers rather than high-stakes testing for students. States and districts that rely on test-based accountability emphasizing sanctions for students and teachers often produce greater failure rather than success for educationally vulnerable students. The paper reviews research on various approaches to accountability and highlights successful reforms in urban settings that emphasize the use of standards for teaching and learning to guide investments in better prepared teachers, higher quality teaching, more performance-oriented curriculum and assessment, better designed schools, more equitable and effective resource allocations, and more diagnostic supports for student learning. It argues for a broader conception of accountability that focuses on whether policymakers' and practitioners' actions, in fact, produce better quality education and higher levels of learning for a greater share of students. It suggests that genuine accountability is achieved when school system policies and operating practices work both to provide good education and to correct problems as they occur. It concludes that raising standards for students so they learn what they need to know requires raising standards for the system. (Contains 69 references.) (SM)