Carter, Ashton B., 1954-

Ashton Baldwin Carter (born September 24, 1954) is an American public policy professor who served as the 25th secretary of defense from February 2015 to January 2017. He is currently Director of the Belfer Center for Science & International Affairs at Harvard Kennedy School.

Carter began his career as a physicist. After a brief experience as an analyst for the Congressional Office of Technology Assessment, he switched careers to public policy. He joined the Kennedy School of Government at Harvard University in 1984 and became chair of the International & Global Affairs faculty. Carter served as Assistant Secretary of Defense for International Security Policy during President Clinton's first term, from 1993 to 1996, responsible for policy regarding the former Soviet states, strategic affairs, and nuclear weapons. During President Obama's first term, he served first as Under Secretary of Defense for Acquisition, Technology and Logistics and then Deputy Secretary of Defense until December 2013. In February 2015, he replaced Chuck Hagel as Secretary of Defense and served until the end of the Obama administration.

For his service to national security, Carter has on five occasions been awarded the DOD Distinguished Public Service Medal. He has also received the CJCS Joint Distinguished Civilian Service Award, and the Defense Intelligence Medal for his contributions to intelligence. Carter is author or co-author of 11 books and more than 100 articles on physics, technology, national security, and management.