Transportation is one of the largest sources of carbon dioxide emissions in the United States and, thus, a critical sector to address in the fight to reduce greenhouse gas emissions. New technological innovations—from the growth in hybrid and electric vehicles, to increases in parcel delivery, to advances in supply change management, to the potential emergence of autonomous vehicles—are rapidly changing the sector. These advancements create the need for new analysis about the role of cars, trains, trucks, and planes and the role transportation will play in energy system decarbonization.   This grant provides funds for a graduate student fellowship program aimed at supporting the work of doctoral students at two universities, University of Maryland and Carnegie Mellon University, who are interested in studying the energy and environmental implications of changes in the U.S. transportation sector. Run by economist Joshua Linn at the University of Maryland and engineer Kate Whitefoot at Carnegie Mellon University, the program will award seven one-year fellowships to early-career scholars wishing to pursue interdisciplinary, policy-relevant transportation research.