Gilbert E. Metcalf is Professor of Economics at Tufts University, Massachusetts, and a Research Associate at the National Bureau of Economic Research. He is also a Research Associate in the Joint Program on the Science and Policy of Global Change at MIT and currently a Visiting Professor in the Department of Economics at MIT where he teaches a class on the economics of energy markets. Professor Metcalf recently served as a member of the US National Academy of Sciences' Committee on Health, Environmental, and Other External Costs and Benefits of Energy Production and Consumption, and the peer-review team of the US Environmental Protection Agency's climate modeling efforts. He has also been a consultant on energy matters to the US Departments of the Treasury and Energy and Argonne National Laboratory. Professor Metcalf also serves on the Advisory Board for the SECURE (Security of Energy Considering Its Uncertainty, Risk, and Economic Implications) Project funded by the European Commission. An associate editor of the Journal of Economic Perspectives and a member of the editorial board of the Berkeley Electronic Journals in Economic Analysis and Policy, Professor Metcalf is the author of more than 70 papers in academic and professional journals, including the Journal of Political Economy, the Economic Journal, the Journal of Public Economics and the Review of Economics and Statistics. He coedited Behavioral and Distributional Effects of Environmental Policy (2001, with Carlo Carraro) and The Distribution of Tax Burdens (2003, with Don Fullerton). Professor Metcalf's primary research area is applied economics with particular interests in taxation, energy and environmental economics.