Most terrorist acts fall into three categories: kidnappings, airplane hijackings, and siege/barricade incidents. In all three instances, the terrorists' primary weapon is the threat of force against their captives. This threat is used in an attempt to gain such objectives as money, increased publicity, and public sympathy for a political cause. Three types of individuals join terrorist groups: fanatics, mentally disturbed persons, and professional criminals. It is noted that (1) the dangerousness of all three types should not be underestimated and (2) terrorists are often successful in manipulating their hostages into developing an attachment for them and their cause, called the 'Stockholm syndrome.' The presentation emphasizes that the current growth of terrorist groups and their actions poses a perplexing problem for governments: How much can any society yield to the terrorists' demands and still survive? Capitulation to terrorists' demands only encourages more terrorism. To lessen this dilemma, the presentation offers steps for both individuals and groups to take to deter terrorism.