Over the last 4 decades, the school effectiveness and school improvement research bases have gained prominence and recognition on the international stage. In both a theoretical and empirical sense, they have matured through a wide range of well-documented projects, interventions, and innovations across a range of countries, describing how efforts to help schools become increasingly effective learning environments for the full range of their students have been more or less successful. This review presents evidence of the effects of reform efforts at the school and system levels, through articulating 5 phases: Phase 1--understanding the organisational culture of the school; Phase 2--action research and research initiatives at the school level; Phase 3--managing change and comprehensive approaches to school reform; Phase 4--building capacity for student learning at the local level and the continuing emphasis on leadership; Phase 5--towards systemic improvement.