In 1968, the PFLP joined the Palestine Liberation Organization (PLO), the main umbrella organization of the Palestinian national movement. The PFLP became the second-largest PLO faction, after Yasser Arafat's own al-Fatah.
PFLP was led by George Habash from 1968 until 2000. At the PFLP's Sixth National Conference he stepped down as general secretary. Abu Ali Mustafa was then elected general secretary.
Mustafa was killed August 27th, 2001 when an Israeli helicopter fired rockets at his office in the West Bank town of Ramallah. Ahmed Sadat was subsequently elected general secretary on October 3rd, 2001. In January of 2002, he was arrested by the Palestinian Authority.
Two factions that broke away from PFLP are Popular Front for the Liberation of Palestine - General Command (PFLP-GC) and Democratic Front for the Liberation of Palestine (DFLP).