Nudge: Improving Decisions about Health, Wealth, and Happiness is a book written by University of Chicago economist and Nobel Laureate Richard H. Thaler and Harvard Law School Professor Cass R. Sunstein, first published in 2008. In 2021, a revised edition was released, subtitled The Final Edition. The book draws on research in psychology and behavioral economics to defend libertarian paternalism and active engineering of choice architecture. The book also popularised the concept of nudge theory. A nudge, according to Thaler and Sunstein is any form of choice architecture that alters people's behaviour in a predictable way without restricting options or significantly changing their economic incentives. To count as a mere nudge, the intervention must require minimal intervention and must be cheap.The book received largely positive reviews. The Guardian described it as "never intimidating, always amusing and elucidating: a jolly economic romp but with serious lessons within." It was named one of the best books of 2008 by The Economist. Source: Wikipedia (en)