Research on the engagement of children with the so-called Islamic State (a.k.a. ISIS) relies heavily on the analysis of obtained ISIS documents and ISIS-disseminated propaganda, leaving major elements of the recruitment and deployment process uncovered. Such ambiguities hinder future efforts aimed at dealing with ISIS’ child soldiers. As such, an intensive effort to compile data using interviews and naturalistic observations across ISIS-held territories in Syria was made to exhaustively explore the process of child recruitment and deployment by ISIS. Findings suggest that there are two methods of recruitment: predatory and structural. The enlistment, intensity of indoctrination, types of training, and nature of deployment were found to depend, to a high degree, on the type of recruitment (i.e., predatory or structural), and category of children based on their origin (i.e., local, Middle Eastern and North African [MENA], or foreign) and if they are orphans. The data shows that the separation between children and adults’ roles/assignments is diminishing. After a thorough exploration of the elements of ISIS’ recruitment and deployment process, this paper argues its findings, implications, and limitations.