After joining the North Atlantic Treaty Organisation (NATO) on February 18, 1952, Turkey signed a Military Facilities Agreement on 23 June 1954, paving the way for a large scale US military presence. With a staff of 1200 by 1959, JAMMAT was the largest of the United States European Commands (USEUCOM), and also the world's largest military assistance and advisory group by 1951. JAMMAT was renamed to Joint United States Military Mission for Aid to Turkey (JUSMMAT) in 1958, and the Office of Defense Cooperation Turkey (ODC-T) () on 1 May 1994.