Secretary of Defense Leon E. Panetta addresses staff members at Walter Reed National Military Medical Center in Bethesda, Md., on Dec. 4, 2012. Panetta thanked the more than 300 attendees for their efforts since Walter Reed Army Medical Center merged with the National Naval Medical Center in August 2011 to create WRNMMC. (DoD photo by Mass Communication Specialist 1st Class Chad J. McNeeley, U.S. Navy/Released)