Terrorist group survival as a measure of effectiveness

Why do some terrorist groups last much longer than others? And what does this longevity tell us about the effectiveness of terrorist organizations? This article argues that organizational survival can be considered one element of organizational effectiveness. The article then reviews the recent literature on terrorist group longevity, including a systematic survey of ten quantitative studies on the subject. Only a few factors are repeatedly associated with longevity, such as group size and participation in terrorist group alliances. Because of theoretical interest in interorganizational relationships, arguments are then considered for why terrorist group alliances, and also intergroup competition, probably contribute to group endurance.