Jim Powell is Senior Fellow at a libertarian think tank, the Cato Institute in Washington, D.C., with which he has been associated since 1988. He has also done work for the Manhattan Institute, the Institute for Humane Studies, Citizens for a Sound Economy, the National Right to Work Committee and Americans for Free Choice in Medicine.

Powell is an author on the history of liberty and its adversaries. His most recent books report findings about the unintended consequences of major presidential policies. He has written eight books and is perhaps best-known for FDR's Folly which has been praised by Nobel Laureates Milton Friedman and James M. Buchanan, Harvard historian David Landes and historian Thomas Fleming. Powell's books have been translated into Japanese. His book Greatest Emancipations, How Slavery Was Abolished In The West is scheduled to be published in June 2008 (Palgrave Macmillan).

He has contributed several hundred articles for an unusually broad array of publications. He has given talks internationally as well as at Harvard, Stanford and other universities across the United States.