Joseph Hart was a banker with Citi Bank and following an assignment in Calcutta, India they returned to Manila in 1950.

He spent two years at Camp Peary in Virginia, attending "the standard two-year course for ... aspiring case officers."

[5] A career Near East Division officer, Hart's overseas postings included five years in India; two years as a Chief of Station (COS) in the Persian Gulf; a three-year posting in Iran, before, during and after the Iranian Revolution (where he was Chief of Station after the Shah fell and the American Embassy was overrun by Khomeini elements); three years as COS Pakistan during the Soviet–Afghan War; and COS, Germany in the period leading up to the collapse of Communism.

He was captured a few days after the Shah's fall by an armed group of supporters of Ayatollah Ruhollah Khomeini, and escaped summary execution by appealing to a mullah, who agreed that the Koran did not sanction such punishment.

Hart jump-started the CIA's efforts to equip the Afghan resistance with weapons and supplies to allow them to mount an effective campaign during the Soviet occupation of Afghanistan.