During the early 1970's when the incidence of hijacking was high, incidents were perpetrated by five general groups: extortionists who parachuted from hijacked planes, homesick Cubans attempting to return to Cuba, terrorists, fleeing felons, and mentally disturbed persons. Methods used to counteract hijackings included developing a security awareness among airport and airline personnel, Government and airline cooperation, use of all available technology, and diplomatic efforts. Security awareness was created by developing local security committees at large airports, security bulletins, and workshops and seminars. Cooperative efforts included intelligence sharing, development of a standard security program, and the frequent interchange of information. Technological developments included the widespread use of metal detectors and x-ray machines, explosive detection K-9 teams, and the use of screening procedures in secure concourses away from boarding gates and under the protection of police officers. Diplomatic efforts have included a hijacking agreement with Cuba in effect from 1973 through 1978; international conferences; and the Bonn Agreement, which sanctions countries harboring hijackers. Recommended future actions include increasing diplomatic efforts for international coordination, improving domestic intelligence, emphasizing prevention, continuing security awareness, developing contingency and crisis management plans, obtaining voluntary press restraints, improving technology, and conducting research on new prevention and deterrence methods. Footnotes, tabular data, a map, and a chart are provided. Appendixes include guidelines for local security committees, forms and a copy of the U.S.-Cuba hijacking agreement.