In the Netherlands, police use IR46 as a Terrorism Risk Assessment Instrument for identifying radicalized individuals and the risk or threat they pose. Originally, its focus was on ideological radicalization as a precursor to terrorist violence. Here, it reflected mainstream thinking in terrorism studies, which held that terrorists overall are ‘normal’ in terms of mental health and socio-economic backgrounds. New empirical research called this ‘normality paradigm’ into doubt, and IR46 has changed accordingly. One example of this research was a 2015 study in Dutch police files describing behavioural problems and disorders in jihadist travelers to the Middle East. This chapter presents new findings from a follow-up study from 2019. The studies, and similar research elsewhere, have indicated that jihadist travelers on average have a history of adverse socio-economic conditions, high criminality, and more mental health problems than their peers. Individual backgrounds may have contributed to their susceptibility to extremist messages. These backgrounds can be quite diverse though, which does not allow for an accurate prediction of those who actually commit a terrorist crime. Nevertheless, insight in these backgrounds provides new angles for identifying and managing risk in individuals of concern.