His research focuses on the consequences of food, energy, agriculture, and natural resource use from a life-cycle perspective. Dr. Hill has testified before U.S. House and Senate Committees on the environmental effects of transportation biofuels. His work has been published in the journals Science and the Proceedings of the National Academy of Sciences. He recently served on the National Research Council’s Committee on the Economic and Environmental Impacts of Increasing Biofuels Production and on the United States Environmental Protection Agency Science Advisory Board’s Biogenic Carbon Advisory Panel.