This compendium of information on terrorist groups, violent international criminal gangs, and other extremist groups that have been or are currently operating is intended for use as a reference guide and research tool for academics, students, government officials, security personnel, military personnel, law enforcement personnel, and the public. The publication also lists and describes political organizations and religious or ethnic factions that espouse violence or display the threat of violence in their philosophical or operational standards. The information was collected from a broad range of sources, including interviews with, law enforcement and military practitioners, researchers and academics, and and government officials. The organizations are listed geographically by continent and country. The listing for each organization covers its stated aims, ideology, or policy; areas of operation, numbers of active members, numbers of supporters, structure, headquarters, leaders' names, funding sources, types of activities, publications, network contacts, significant actions and activities, and trends.