Armed groups play a central role in conflicts today and are associated with many of the humanitarian concerns generated by conflicts. Political and humanitarian players intent on promoting respect for the rights of conflict victims must set aside resources to study and understand armed groups, grasp the law that applies to them, and assess its limits. To this end, a pragmatic approach may be necessary, taking the perspective of armed groups into consideration rather than seeing them merely as an anomaly in an international system designed by and for States.