Ramzi Yousef is serving a life term, without the possibility of parole, for the 1993 World Trade Center bombing. He is the nephew of Khalid Sheikh Mohammed (KSM), who was to become the operational commander of the 9-11 attack. Like his uncle, he came from the Balochistan Province of Pakistan.
He was part of an evolving worldwide network of terrorists conducting a jihad for their view of Islam. Steve Coll suggests his motivation was less a complex theological one, but more directed at the United States as an enemy due to its support of Israel. He was affiliated with people active in the Muslim Brotherhood, but his focus was more on anti-Israeli issues.  Laurie Mylroie theorizes that he was operating under Iraqi sponsorship, , although this was not suggested at the trial, and Richard Clarke describes her theory as discredited.
Yousef was captured in Pakistan, after police in the Philippines uncovered Operation BOJINKA, a plan, put together with KSM, for detonating bombs near-simultaneously aboard 12 airliners flying across the Pacific.
- Steve Coll (2004), Ghost Wars: The Secret History of the CIA, Afghanistan, and Bin Laden, from the Afghan Invasion to September 10, 2001, Penguin, pp. 250-251
- "The World Trade Center Bomb: Who is Ramzi Yousef? And Why It Matters", The National Interest, Winter 1995/96
- Richard A. Clarke (2004), Against all Enemies: Inside America's War on Terror, Free Press, Simon & Schuster, ISBN 0743260244, p. 95