Source: (2006) International Journal of Offender Therapy and Comparative Criminology. 50(2): 121-138.Part I of this two-part article describes the major forms of domestic and foreign terrorism, the motivations of the perpetrators, and the psychological, social, and political forces that contribute to this most particular expression of violence. The article addresses the question of whether all terrorists are sick or evil and considers the possibility that some forms of terrorism, however odious their result, can be a rational response to a situation of perceived intolerable injustice. The article examines what motivates people to join terrorist groups and what may later move them to leave the terrorist lifestyle. Special consideration is given to the psychological and religious dynamics of suicide terrorism and what might motivate some people to give their lives for their cause. Finally, the article offers recommendations for a multipronged approach to dealing with this modern yet ageless scourge.