Almost all Army colonels have attended a war college or a senior staff college equivalent to study joint warfare and war itself. Most Army colonels receive postgraduate level senior joint professional military education (JPME) at the Army War College in Carlisle, Pennsylvania prior to promotion. The 2009 graduating class was 336 including 198 army officers and the rest divided among other military branches, domestic inter-agency representatives and other foreign military leaders. The highest concentration of USAF colonels graduate from the Air War College at Maxwell AFB, Alabama via in-residence at Maxwell AFB. This program will include participation by officers from various other branches. Marine colonels may graduate from the Marine War College or, like all other branches, may receive credit via non-resident attendance at another installation, via correspondence, or will be graduates of an equivalent senior JPME program sponsored by the National Defense University or one of the other U.S. military services.