Editors’ Introduction E.A. Hanushek*, S. Machin†, L. Woessmann *Stanford University, NBER, and CESifo †University College London; Centre for Economic Performance, London School of Economics; and CESifo {University of Munich, Ifo Institute, and CESifo That a fifth Handbook of the Economics of Education is now complete testifies to the substantive and influential body of research on education now being produced by economists. The ten original contributions to the volume cover a wide range of key, topical education research questions. In doing so, they draw upon research findings using a blend of economic theory and modern empirical methods. As with prior volumes, each of the chapters has a forward looking perspective. While they review the current state of the art in each area, they use this as a building block in pointing to current puzzles and useful places for further development. Two things have changed, however, in the decade since the first volume was published. First, the research base — as we describe briefly below — has dramatically expanded in many of the overall areas covered. Second, with this expansion, the range of topics worthy of inclusion has itself expanded. It is useful to place this work within the broader field of economics. The economics of education has become one of the most active areas of applied economic research. All top economics departments have individuals working in the area, and many economics of education researchers are now employed in positions in education and public policy schools. Papers on education now frequently appear in the profession’s leading academic journals. The numbers in the following table make clear this publication trend. It shows decade by decade numbers, starting in the 1950s and going up to the first decade of the millennium, for a word-search-based measure of the number of economics of education papers published in top economics journals. It rises from just 3 in the 1950s to 134 by the 2000s. Education publications in selected general-interest economics journals Decade 1950s 1960s 1970s 1980s 1990s 2000s Number of papers 3 37 78 38 82 134 Number non-North American based 0 4 13 8 23 56 Percent non-North American based 0% 11% 17% 21% 28% 42% Notes: Publications with the word Education, Schooling, School, or Human capital in the title in the following list of journals: American Economic Review; Economic Journal; Econometrica; Economica; Journal of Political Economy; Quarterly Journal of Economics; RAND Journal of Economics; Review of Economic Studies. Source: Machin (2014). The very clear internationalization of the area is also made clear, as the percentage of papers written by authors outside of North America rises from none of the three in the 1950s to 42% of those in the 2000s. There are a number of reasons that lie behind this rise to prominence, and why it looks set to continue. One key factor has been the increased call from governments around the world to design evidence-based education policies. The nature of evidence provided via education research by economists is very well suited to meet this policy demand. Over and above this, the data available to study education have improved massively through time. The kinds of administrative data sources that are almost routinely used in much of today’s research simply were not available two or three decades ago. Nor was the richness of survey data available for analysis of international differences in test scores now collected on pupils in a very large number of countries around the world (Hanushek and Woessmann, 2011). These are but two examples of the provision of more and better data available for education research. Moreover, it is clear that the influx of new data has dovetailed particularly well in economics of education research with the methodological advances that have been made in empirical economics. The study of experimental settings and a range of “quasi” or “natural” experiments that have been used to push the research frontier forwards have featured a lot in the new economics of education research. These enablers of economics of education research have by now drawn in many new cohorts of researchers who have begun their academic research careers doing a Ph.D. on the economics of education, and subsequently become academics, policymakers, and education practitioners. This vibrant, and now sizable, young group of economists work- ing on education augurs well for the economics of education field to continue to thrive in the future. Volume 5 of the Handbook of the Economics of Education features ten chapters on con- temporary issues in education. A couple of chapters, while ostensibly covering the same general areas as chapters in earlier volumes (ie, student loans and education in developing countries), underscore the dramatic advances in the fields over the past decade. However, the majority of the volume goes into new areas, for some of which (eg, technology, behavioral approaches, and teacher pensions) there was virtually no literature available a decade ago. Handbook volumes appear at irregular intervals, but the explosion of research and articles in the economics of education suggest that this is not the last volume in the series. REFERENCES Hanushek, E., Woessmann, L., 2011. The economics of international differences in educational achieve- ment. In: Hanushek, E., Machin, S., Woessmann, L. (Eds.), Handbook of the Economics of Education, vol. 3. Elsevier, Amsterdam. Machin, S., 2014. Developments in economics of education research. Labour Econ. 30, 13–19. European Association of Labour Economists Special 25th Memorial Issue.