The study of terrorism has now arrived internationally, as evidenced by the birth of a new international multidisciplinary journal, Terrorism; the proliferation of scientific conferences and papers; and the growth of university research and teaching on the subject. Historians, social scientists, lawyers, criminologists, administrators, and political leaders are showing an increasing awareness of the need for more informed scholarly analysis of the growing international incidence of acts of terrorism perpetrated by extremist groups of almost every ideological hue and in every continent.