Published data were analyzed for over 350 terrorist cadres and leaders active during 1966-76. Terrorists are largely single males aged 22 to 24 who have some university education, if not a college degree. Female terrorists, with exceptions for some groups, perform supportive rather than operational roles. Urban terrorists generally come from affluent, urban, middle-class families, many of whom enjoy considerable social prestige. Many terrorists have practiced in prestigious professions prior to becoming terrorists. Most have been strongly influenced by an anarchist or Marxist world view and were recruited into terrorist operations while in college. In a number of countries, younger persons are being recruited to terrorism. Increasing numbers are trained in skilled trades. Future research must determine whether this trend will alter the terrorist profile. 24 footnotes.