This collection of papers presents the debate between supporters and critics of the school effectiveness movement. School effectiveness research explores the different contributions schools make to pupils' learning and the factors that make some schools more successful than others. Politically influential, helping to shape the education policies of the two main parties, it has also been used at a practical level to generate programmes and policies for school improvement. Members of the Institute of Education's School Effectiveness and Improvement Centre (ISEIC), which leads the field in research in this area, contribute papers to this volume that both describe the research and reply to criticisms of it, while other contributors from both within and outside the Institute provide philosophical, sociological and cross-cultural critiques, which are challenged in an Endpiece by Peter Mortimore and Pam Sammons.