Adam S. Posen has been president of the Peterson Institute for International Economics since January 2013, after first joining in July 1997. Over his career, he has written about the financial and economic challenges faced by the European Union following the adoption of the euro, the lasting impact of Japan's economic crisis of the 1990s, and monetary and fiscal policies in the G-7. While at the Federal Reserve Bank of New York during 1994–97, he coauthored Inflation Targeting: Lessons from the International Experience with Ben Bernanke and others. He was one of the first scholars to seriously address the political foundations of central bank independence.

In September 2009, Posen was appointed by the UK Chancellor of the Exchequer to serve a three-year term as an external voting member of the Bank of England's rate-setting Monetary Policy Committee (MPC). During this critical period for the world economy, Posen advocated an activist policy response to the financial crisis, led the MPC into quantitative easing, supported efforts to stimulate business investment, and accurately forecasted global inflation developments. Leading up to the successful London G-20 summit of 2009 during the global financial crisis, he consulted for the UK Cabinet Office.

Posen received his BA and PhD from Harvard University. In addition to his leadership at the Institute, Posen advises the US Congressional Budget Office. He is a member of the Council on Foreign Relations and the Trilateral Commission.

Posen has been the recipient of major grants and research fellowships from the American Academy in Berlin, the Bank of England, the Brookings Institution, the European Commission, the Ford Foundation, the Sloan Foundation, and the US National Science Foundation. He has been widely profiled and interviewed by leading news organizations, including Bloomberg, the Wall Street Journal, New York Times, Washington Post, and Financial Times. His op-eds have appeared in many publications, and he has served as a columnist for the Financial Times.