The study has several limitations that should be recognized when interpreting the results. First, findings might not be generalizable to the general population since only individuals who have traveled internationally or have demonstrated an interest to visit international destinations were sampled. Second, findings might be limited by the nature of the sampling frame. A list of names, comprising individuals who previously responded to tourism- related surveys or who contacted travel professionals for information, was obtained from a mail list broker. Because it is virtually impossible to determine all circumstances relevant to the compilation of the mail list, inferring study findings to the general public is not recommended. Third, study findings might not be generalizable to non-US populations, since the investigation was conducted in the United States. Subjects' responses could be influenced by their cultural backgrounds as well as their social/cultural environment. Such responses might be different according to the environment in which the investigation is conducted. Cultural differences in risk perception magnitude and source of perceived hazards have been found in cross cultural studies of perceived risk (Goszczynska, Tyszka and Slovic 1991; Mechitov and Rebrik 1990; Tiegen, Brun and Slovic 1988). Fourth, subjects' perceptions of terrorist threat might be heightened by print and broadcast media coverage of current terrorist events and/or political instability or, to the contrary, such perceptions might be diminished by the lack of current terrorism and/or political instability. Thus, the absence of relevant publicized events during the study's investigative process might have influenced responses to the research questionnaire. Moreover, internal factors measured in this study might not fully represent all of the influences on international vacation decisions and their outcomes. For example, intensive marketing activities by a particular destination could overcome perceived threats of terrorism.