This book brings together the results of more than five years of research conducted by the Center for Energy and Environmental Policy Research at the Massachusetts Institute of Technology, with which all of the authors have been affiliated. The Center seeks to provide rigorous, empirically grounded, and accessible economic analysis to inform the public policy debate. It has been the focus of applied economics research on energy and environmental issues at MIT for more than twenty years. The Center historically has concentrated on topics – like emissions trading – that are both interesting to academics and relevant to policymakers and industry analysts. Market-based emissions control instruments are increasingly in vogue, and we are pleased to provide this evaluation of the remarkable public policy experiment with emissions trading that was initiated by Title IV of the 1990 Clean Air Act Amendments, the U.S. Acid Rain Program. We hope that our research will contribute to the consideration of market-based systems as tools for meeting at least some demands for environmental amenities.

As is the case for any major endeavor, there is a long list of people without whose assistance this book would never have appeared. This research has grown out of the inspired suggestion and accompanying funding by the National Acid Precipitation Assessment Program (NAPAP), which initially encouraged us to combine our collective experience to provide an evaluation for NAPAP's Quadrennial Report to the U.S. Congress.