Marc Sageman is an independent researcher on terrorism and the founder of Sageman Consulting, LLC. He holds various academic positions at the University of Pennsylvania, the University of Maryland, and at think tanks such as the Foreign Policy Research Institute. After graduating from Harvard University, he obtained an M.D. and a Ph.D. in sociology from New York University. Subsequent to a tour as a flight surgeon in the U.S. Navy, he joined the CIA in 1984. He spent a year on the Afghan Task Force and then went to Islamabad from 1987 to 1989, where he ran the U.S. unilateral programs with the Afghan Mujahideen, and New Delhi from 1989 to 1991. In 1991, he resigned from the agency to return to medicine. He completed a residency in psychiatry at the Hospital of the University of Pennsylvania. Since 1994, he has been in the private practice of forensic and clinical psychiatry and has had the opportunity to evaluate about 500 murderers. After 9/11, he started collecting biographical material on about 400 al Qaeda terrorists to test the validity of the conventional wisdom on terrorism. This research has been published as Understanding Terror Networks (University of Pennsylvania Press, 2004). He may be the only individual to have testified before both the 9/11 Commission in the United States and the Beslan Commission in Russia. As an expert on al Qaeda and related terrorist organizations, he has consulted with various branches of the U.S. government, including the National Security Council, the Department of Defense, the Combatant Commanders, the National Laboratories, the Department of Homeland Security, various agencies in the U.S. Intelligence Community, and various law enforcement agencies. He has lectured at many universities here and abroad, including Harvard, Pennsylvania, MIT, Chicago, Michigan, California-Berkeley, and Johns Hopkins. He has also consulted with foreign governments (France, Australia, Spain, Canada, Germany, and the United Kingdom).