Dr. Greene's work applies interdisciplinary research findings to national transportation energy and environmental policy. Over the years, he has made significant contributions to energy policy research and analysis for transportation, and for advancing understanding of the transportation sector's role in energy and environmental concerns. He is the lead author for the Intergovernmental Panel on Climate Change (IPCC)'s Second, Third, and Forth Assessment Reports. His recent research focuses on modeling energy transitions for the transportation sector and the macro-economic impacts of the future oil crisis. Dr. Greene has published more than two hundred professional publications, including three books (Transportation and Energy, Transportation and Global Climate Change, and The Full Costs and Benefits of Transportation). In recognition of his service to the National Academy of Science and National Research Council, Dr. Greene has been designated a lifetime National Associate of the National Academies.