This study assumes that political terrorism results from conscious decision-making by groups opposing a governing system, policy or process. The kinds of terrorist activity employed depend upon such factors as the philosophy, goals, objectives, and needs of the terrorist group. This presents a comparative analysis of three types of terrorists in southwest Asia: Palestinians, Marxist-Leninists, and Muslims. The first section summarizes and compares the three groups' motivational causes, philosophies, histories and sources of inspiration. The second section compares their behavior from four perspectives: trends and patterns, level of violence, tactical preferences, and lethality. The third section identifies and categorizes socioeconomic, political and military variables associated with tactic selection and acts of terrorism.