The Abu Nidal Organization (ANO) is the most common name for the Palestinian nationalist militant group Fatah – The Revolutionary Council (Fatah al-Majles al-Thawry). The ANO is named after its founder Abu Nidal. It was created by a split from Yasser Arafat's Fatah faction of the PLO in 1974. The group has been designated as a terrorist organization by the United States, the United Kingdom, Japan, Israel, Canada, and the European Union.

The ANO was secular and anti-Western, but was not particularly associated with any ideology, or at least no such foundation was communicated. The organization was strongly linked with Abu Nidal's personal agenda. The group carried out hijackings, assassinations and kidnappings of diplomats, and attacks on synagogues – 90 attacks during the period 1974–1992. Nidal died in Baghdad in 2002.