Research shows that, historically, relatively few returning foreign terrorist fghters (FTFs) posed
a direct threat. However, those that did were responsible for some of the most lethal terrorist
attacks carried out over the past three decades. FTFs have also played a critical role in creating
and strengthening terrorist groups, and radicalizing and recruiting terrorist networks.

The current FTF wave has clear diferences with previous ones. Studies indicate that it is larger,
more global, and more diverse in terms of age, gender and experience in the confict zones.
Tese diferences make the potential challenges associated with returnees and relocators signifcantly bigger, but also more complex.