This handbook provides the most comprehensive international review of the school effectiveness and school improvement research in the twenty five years since the disciplines became prominent. The handbook contains chapters, not only from most of the key contributors to this research from the USA, the UK, Hong Kong and Europe, but also contains a number of chapters that document the progress of the field in regions of the world that are less known, including the Asian-Pacific region, Latin America, Africa and the Middle East. It contains the thoughts of not only the proponents of school effectiveness research, but those that have been critical of it. It documents the progress of the field over the past quarter century and clearly identifies the improvements in research techniques and the ability to consider context as a major feature. It provides both theoretical constructs and practical applications and case studies that are transnational and those that are local. Finally, it provides some possibilities for future research, policy and practice to guide the discipline into the next decade of change. The handbook provides a state of the art analysis of the complex issues facing schools, school systems, societies and nations that will support researchers, policy makers and practitioners in their search for ways to provide a high quality education to all students.