The Palestine Liberation Organization (PLO; Arabic: منظمة التحرير الفلسطينية, Munaẓẓamat at-Taḥrīr al-Filasṭīniyyah) is a Palestinian nationalist political and militant organization founded in 1964 with the initial purpose of establishing Arab unity and statehood over the territory of former Mandatory Palestine, in opposition to the State of Israel. In 1993, alongside the Oslo I Accord, the PLO's aspiration for Arab statehood was revised to be specifically for the Palestinian territories under an Israeli occupation since the 1967 Arab–Israeli War.

It is headquartered in the city of Al-Bireh in the West Bank, and is recognized as the sole legitimate representative of the Palestinian people by over 100 countries that it has diplomatic relations with. As the official recognized government of the de jure State of Palestine, it has enjoyed observer status at the United Nations (UN) since 1974. Due to its militant activities, including acts of violence primarily aimed at Israeli civilians, the PLO was designated as a terrorist organization by the United States in 1987, although a later presidential waiver has permitted American contact with the organization since 1988. In 1993, the PLO recognized Israel's right to exist in peace, accepted Resolution 242 of the United Nations Security Council, and rejected "violence and terrorism". In response, Israel officially recognized the PLO as a legitimate authority representing the Palestinian people. However, despite its participation in the Oslo Accords, the PLO continued to employ tactics of violence in the following years, particularly during the Second Intifada of 2000–2005. On 29 October 2018, the Palestinian Central Council suspended the Palestinian recognition of Israel, and subsequently halted all forms of security and economic cooperation with it.