Nathaniel Keohane is an economist, advocate, and recognized expert on climate, environment, and energy issues. He is a Vice President at Environmental Defense Fund (EDF),a leading nonprofit advocacy organization based in New York, where he leads EDF’s International Climate program and helps to shape the organization’s advocacy for environmentally effective and economically sound climate policy. In 2011-2012, he served in the Obama Administration as Special Assistant to the President for Energy and Environment in the National Economic Council and Domestic Policy Council, where he helped to develop and coordinate administration policy on a wide range of energy and environmental issues. Prior to joining the Administration, Keohane was Director of Economic Policy and Analysis and then Chief Economist at EDF, playing a lead role in efforts to enact comprehensive cap-and-trade legislation in Congress. Before joining EDF in 2007, Keohane was an Associate Professor of Economics at the Yale School of Management. His research in environmental economics has appeared in prominent academic journals, and he is the co-author of Markets and the Environment (Island Press, 2007) , and co-editor of Economics of Environmental Law (Edward Elgar, 2009).