Data for the report were collected and computerized by Tel Aviv University's Jaffee Center for Strategic Studies (JCSS). The JCSS terrorism data base contains files on terrorist events, terrorist groups, and government attitudes toward terrorism. A total of 437 international terrorist incidents were recorded in 1986, an increase of 7 percent over 1985. Three types of terrorist acts accounted for 93 percent of the incidents: bombing, armed assault, and kidnaping. Bombings represented 50.6 percent of all terrorist incidents, a small decrease from 50.6 percent in 1985. Armed assaults comprised 31.8 percent of all incidents, an increase over 23.5 percent in 1985. Kidnapings accounted for 10.5 percent of all incidents, a decrease from 13.2 percent in 1985. Two-thirds of the incidents occurred in nine countries: Lebanon, Peru, Colombia, Spain, Germany, Pakistan, France, Greece, and the Netherlands. Of the 437 incidents, 9.3 percent involved actual or attempted assassinations, 10.8 percent involved random killings, 19 percent were aimed at killing and causing property damage simultaneously, 40 percent were apparently intended to cause only property damage. and 5.5 percent involved extortion. Business facilities and executives constituted the single most common terrorist target, followed by political targets. Direct victims of international terrorism included 398 dead, 1,118 wounded, 282 kidnaped, 325 hijacked, and 407 held hostage. The total number of victims in 1986 (2,530) was not markedly different from that in 1985 (2,642). Although 51 terrorist groups were involved in international terrorist activities in 1986, more than half of the incidents were perpetrated by about 12 organizations, primarily in the Middle East, Europe, and Latin America. Nearly 11 percent of all international terrorism was state-sponsored. A chronology of significant international terrorist events in 1986 and a glossary of terrorist organizations are included. 22 tables