This book presents a thorough economic analysis of both the determinants and the consequences of international differences in schooling quality. It is shown that cross-country differences in quality-adjusted human capital can account for a substantial part of the international variation in economic development. However, large increases in per-student spending over recent decades were not matched by increases in student achievement in most countries. In a simple principal-agent model, the book stresses the importance of institutional features of the schooling system such as central examinations, school autonomy, and private-sector competition. Microeconometric estimations based on data for more than a quarter of a million students reveal that international differences in these institutions, rather than differences in resources, can explain the large international differences in schooling quality.