Cass R. Sunstein is an American legal scholar, author, and professor at Harvard Law School. He is the Robert Walmsley University Professor at Harvard, where he specializes in constitutional law, administrative law, environmental law, and law and behavioral economics. Sunstein has written numerous books and articles, including the best-selling Nudge: Improving Decisions About Health, Wealth, and Happiness. He has served in the Obama administration as Administrator of the White House Office of Information and Regulatory Affairs, and as a member of the President's Review Group on Intelligence and Communications Technologies. Sunstein is a leading figure in the field of law and economics, and his work has been widely cited in legal decisions and academic journals.