This volume is a follow-up to the earlier Urban Economics, Volume 2 of Handbook of Regional and Urban Economics, edited by Edwin Mills. The earlier volume, published in 1987, focussed on urban economic theory. This new handbook, in contrast, focuses on applied urban research. The difference is of course in emphasis. The earlier volume was by no means entirely concerned with theoretical research and this one is by no means entirely concerned with applied research.

There have certainly been important theoretical developments during the last decade, and they are surveyed at appropriate places in this volume. However, there has been an outpouring of high quality applied research in urban economics, as in other specialties. The reasons for the rapid growth of applied research are not difficult to identify; improved theoretical frameworks within which to do applied research; improved econometric techniques and software; more and better data; and, probably most important, ever cheaper computing power, which is being ever more widely distributed within the research community, providing increasingly easy access to and analysis of, data.

Selection and classification of topics to include in this handbook has inevitably depended on the editors' perceptions of subjects on which important research has been undertaken. It has also depended on the availability of authors who were able and willing to write critical surveys of large amounts of international research. An attempt was made to include authors and have them survey research from a variety of countries. However, there is still a US bias in applied urban research, partly related to the availability of dataand computers but also to the sheer size of the US research community.