Since the September 11 terrorist attacks on the United States, terrorism has gained increased prominence in both scholarship and the media. While international terrorist acts are quite visible and highly publicized, such attacks represent only one type of terrorism within the international system. In fact, a very large number of acts of terrorism take place within the context of civil wars. Given the great disparity in power in most civil wars, it is not surprising that terrorism might be seen as a tactic that is often used by insurgent groups, who may have few resources at their disposal to fight a much stronger opponent. There is a clear linkage between the concepts of terrorism and civil war, yet until recently scholars have largely approached civil war and terrorism separately. Recent literature has attempted to specifically map the intersection of terrorism and civil war, recognizing the extent to which the two overlap. As expected, the findings suggest that civil war and terrorism are highly linked. Other scholars have endeavoured to explain why rebel groups in some civil wars use terrorism, while others do not. Further research focuses on how governments respond to terrorism during civil war or on how the decisions of external actors to intervene in civil wars are affected by the use of terrorism by insurgent groups. These studies show that there is too little theorizing on the relationship between civil war and terrorism; while scholars are finally considering these concepts collectively, the full nature of their relationship remains unexplored. Additional research is needed to better understand the various ways that terrorism and civil war overlap, interact, and mutually affect other important international and domestic political processes.