Donald Worster is the Hall Distinguished Professor of American History at the University of Kansas. A leader in the field of environmental history, his research areas include North American environmental history, the history of the American West, the history of evolution, ecology, and exploration, and 19th- and early 20th-century U.S. history. As a leader in the field of environmental history, he has served as president of the American Society for Environmental History, sits on a number of editorial boards, and is general editor of the Cambridge University monograph series, "Studies in Environment and History." He has published numerous works, including A River Running West: The Life of John Wesley Powell (Oxford University Press, 2001), for which he won the Byron Caldwell Smith Award; Rivers of Empire (1985) which deals with the development of water resources in the West and was nominated for the Pulitzer Prize; Dust Bowl (1979), a study of the Southern Plains in the "dirty thirties," which won the Bancroft Prize; and Nature's Economy (1994, second edition), which traces the evolution of ecology from the eighteenth century to the present. Worster has also received numerous honors, fellowships, and awards, among which are the Distinguished Achievement Award from the Society for Conservation Biology (1997)-he is the first no-nscientist to receive it; a Guggenheim Fellowship (1981-82); and American Council of Learned Societies Fellowship (1975-75); and a Mellon Fellowship at the Aspen Institute for Humanistic Studies (1974).