Bruce Hoffman is a professor at Georgetown University's Walsh School of Foreign Service and the director of its Center for Security Studies and the Security Studies Program as well as a senior fellow at the U.S. Military Academy's Combating Terrorism Center. He was scholar-in-residence for counterterrorism at the Central Intelligence Agency from 2004 to 2006 and is the author of the highly praised Inside Terrorism. Fernando Reinares is a professor of political science and security studies at Universidad Rey Juan Carlos as well as a senior analyst on global terrorism at Elcano Royal Institute in Madrid, Spain. Between 2004 and 2006, he served as senior advisor on counterterrorism policy to Spain's Ministry of Interior. He is the author of two Spanish best-sellers on ETA and the Madrid train bombings respectively.