The recruitment, radicalization, travel, and return of opposition foreign fighters to Syria and Iraq pose unique challenges at home and abroad in both the short and long term. In an effort to shed more light on the nature of this problem, the Combating Terrorism Center (CTC) at West Point collected a large dataset of open source information on individuals who attempted or successfully traveled to Syria and Iraq from 2012-2015 to join one of the many groups opposing the Bashar al-Assad regime, with a focus on fighters coming from Western countries. The goal of this collection was not to create a master list of all foreign fighters, but to see how information in the open source could shine light on the three stages of what the CTC refers to as the foreign fighter lifecycle: pre-departure, in theater, and return. In examining the entire lifecycle, the goal was to paint a picture of the depth and nuance of the overall threat. In doing so, several key findings emerged. Some of these findings reinforce existing understanding of the foreign fighter problem, while others provide new insights into the challenging nature of this issue.