Scott Barrett was the first Harvard University Center for the Environment Visiting Scholar, in April 2007. He was hosted during his visit by Prof. Robert Stavins, Director of the Harvard Environmental Economics Program, and participated in several meetings and seminars with Harvard economics faculty and Ph.D. students. Prior to joining Columbia in the fall of 2009, Barrett served on the faculty of Johns Hopkins University's Paul H. Nitze School of Advanced International Studies. He is the author of Environment and Statecraft: The Strategy of Environmental Treaty-Making (Oxford University Press 2005) and numerous research and policy papers on climate change. He has also advised a number of international bodies on the subject, including different agencies of the United Nations, the European Commission, the OECD and, most recently, the International Task Force on Global Public Goods. He was a lead author of the second assessment report by the Intergovernmental Panel on Climate Change and was previously a member of the Academic Panel of Environmental Economists to the UK’s Department of Environment. He received his PhD in economics from the London School of Economics. His latest book, Why Cooperate? The Incentive to Supply Global Public Goods, will be published by Oxford University Press in September 2007. Prof. Barrett has also written a chapter for Architectures for Agreement: Addressing Global Climate Change in the Post-Kyoto World, edited by Prof. Stavins and Joseph Aldy, Fellow at Resources for the Future, to be published by Cambridge University Press in August 2007.