The People's Mojahedin Organization of Iran (PMOI), also known as Mojahedin-e-Khalq (MEK) or Mojahedin-e-Khalq Organization (MKO) (Persian: سازمان مجاهدين خلق ايران, romanized: sâzmân-e mojâhedīn-e khalq-e īrân), is an Iranian political-militant organization. It advocates overthrowing the Government of the Islamic Republic of Iran and installing its own government. Its revolutionary interpretation of Islam contrasts with the conservative Islam of the traditional clergy as well as the populist version developed by Ayatollah Khomeini in the 1970s. It is also Iran's largest and most active political opposition group. The MEK was founded on 5 September 1965 by leftist Iranian students affiliated with the Freedom Movement of Iran to oppose the U.S.-backed Shah Mohammad Reza Pahlavi. The organization engaged in armed conflict with the Pahlavi dynasty in the 1970s and contributed to the overthrow of the Shah during the 1979 Iranian Revolution. It subsequently pursued the establishment of a democracy in Iran, particularly gaining support from Iran's middle class intelligentsia. After the fall of Pahlavi, the MEK boycotted the December 1979 Iranian constitutional referendum and Khomeini prevented Massoud Rajavi and other MEK members from running for office. By 1981, authorities had banned the MEK and begun a major crackdown on the group's members and supporters, driving the organization underground.

People's Mojahedin Organization of Iran - Wikipedia