Is there a direct connection between demography and the occurrence of terrorism? The answer is no. There are, however, several important indirect links which make it worthwhile, in a study on the future of terrorism, to examine demographic trends and international migration patterns. For example, rapid population growth usually skews the age pyramid in favour of young people, and violence – both political and criminal – is overwhelmingly the work of young males. Hence, societies that have a disproportionately high density of youth turn out to be more predisposed to high levels of violent conﬂicts than comparable societies with a much older population.2 Similarly, high ‘sex-ratio societies’, where there are far more males than females, are also likely to experience higher levels of violence than similar countries without a skewed gender balance.3 Furthermore, unlike guerrilla warfare, terrorism is predominantly an urban phenomenon, and states undergoing rapid urbanisation are therefore likely to provide a more facilitating environment for terrorist organisations compared to countries in which the society remains largely premodern and rural. Finally, international migration, which will be examined in the last part of this chapter, has the potential to rapidly change the ethnic compositon of a country and thereby unleash violent responses. Fleeing from repressive regimes and civil wars, international migrants also tend to link their new host countries more closely to distant conﬂict zones and the various terrorist and insurgent groups operating there.