Carter Congratulates Dempsey Defense Secretary Ash Carter shakes hands with Army Gen. Martin E. Dempsey, 18th chairman of the Joint Chiefs of Staff, at Dempsey's retirement and change of responsibility ceremony on Joint Base Myer-Henderson Hall, Arlington, Va., Sept. 25, 2015. Marine Gen. Joseph Dunford succeeds Dempsey as the 19th chairman of the Joiunt . DoD photo by Petty Officer 2nd Class Dominique A. Pineiro SHARE: Download: Full Size (1.19 MB) Tags: defense secretary, cjcs, martin e. demspey, ash carter, all images Credit: Petty Officer 2nd Class Dominique Pineiro VIRIN: 150925-D-PB383-012.JPG Photo Gallery