William Vickrey was a Canadian economist known for his contributions to the field of economics, particularly in auction theory and public economics. He was awarded the Nobel Prize in Economic Sciences in 1996 for his work on incentive theory, which explores how to design systems that encourage individuals to act in socially beneficial ways. Vickrey's most notable concept is the Vickrey auction, a type of sealed-bid auction where the highest bidder wins but pays the second-highest bid. This innovative approach helps to ensure that bidders reveal their true valuations, leading to more efficient outcomes in various economic scenarios.