The ship was assigned to foreign service and, after fitting out, departed Philadelphia 20 August 1920 for Newport, Rhode Island, where she took on torpedoes and fuel, and on the 28th got underway for the Mediterranean area. She arrived at Constantinople, Turkey, 21 September reporting for duty with U.S. Naval Detachment Operating in Turkish waters. "Fox" cruised in the eastern Mediterranean and Black Sea until July 1922, visiting various ports of Turkey, Greece, Palestine, Syria, Asia Minor, Romania, Russia and Egypt. At a time of disturbed conditions throughout the Near East and southern Russia she rendered aid to American commercial men, relief and Red Cross workers, and Food Administration officials; transported mail, dispatches, and passengers; served as station ship at various ports; and assisted in the evacuation of refugees from Crimea.