In terms of its disruptive impact and intensity of violence, banditry is the gravest security threat that Nigeria currently faces, and it is driving her worst national humanitarian crisis in decades. There are contests about the origin, nature and the drivers of banditry and how well bandits by their modus operandi fit into the various definitional frameworks of an organized criminal group. The article examines what is known about bandits and banditry in light of existing definitional and conceptual paradigms of organized crime and criminal groups, and interrogates the applicability of international humanitarian law to this security crisis that characterizes the current face of conflict in the West African Sahel.