Professor (2008), Associate Professor (2001), Assistant Professor (1999)  Department of Economics, Rutgers University, New Brunswick

Assistant Professor, Department of Economics, UCLA, 1992-1998

Visiting Scholar, Copenhagen Business School, 2007

Visiting Associate Professor, Ford School of Public Policy, University of Michigan, 2002

Visiting Fellow, Hoover Institution, Stanford, CA, 1998

Research Associate (2008–) and Faculty Research Fellow (1994–2008), National Bureau of Economic Research (NBER)

Board of Directors (2003–2005) and Nominating Committee (2007), Association of Environmental and Resource Economists (AERE)

Editorial Council, Journal of Environmental Economics and Management, 1997-2004

Editorial Council, Public Finance Review, 2003-

Co-organizer, NBER Summer Institute Environmental Economics and Policy Workshop,  2003

Reviewer for National Science Foundation, Social Science and Humanities Research Council of Canada, National Research Council, and many academic journals and publishers

Research presentations since 2009: Society for Environmental Law and Economics; American Economic Association Annual Meeting;  Association for Public Policy Analysis and Management Annual Meeting; World Congress of Environmental and Resource Economists IV;  NBER Conference, “The Design of U.S. Climate Policy”; Conference on Empirical Legal Studies; Latin American and Caribbean Law and Economics Association Annual Meeting; Yale University

Environmental Economics Advisory Committee, Science Advisory Board, U.S. Environmental Protection Agency (EPA), 1998-2004

UST/RCRA Benefits, Costs, and Impacts Review Panel, Science Advisory Board, U.S. EPA, 2002

Executive Committee, Graduate School-New Brunswick, Rutgers University, 2009-2012

Board, Rutgers Energy Institute, 2009-present