Vice Adm. Matthew Nathan, Navy surgeon general, speaks during the second day of plenary sessions during the 2012 Military Health System (MHS) Conference held at the Gaylord National Hotel and Convention Center in National Harbor, Md., Feb. 1, 2012. The MHS aims to ensure the medical readiness of U.S. service members, and to provide a ready medical force. (DoD photo by Johnny Bivera, DoD)