This landmark book argues that methods reasonable for measuring gains and losses for a generation into the future may not be appropriate when applied to a longer span of time. Paul Portney and John Weyant have assembled some of the world's foremost economists to reconsider the purpose, ethical implications, and application of discounting in light of recent research and current policy concerns. First Published in 1999. Routledge is an imprint of Taylor & Francis, an informa company.