Private military enterprises and individual mercenaries have played a key role in warfare for much of history. This was especially the case until the rise of the European nation-states, when private military actors saw a decline in demand for their services. However, the end of the Cold War marked a turning point for the profession and a nascent private military industry that is today valued at hundreds of billions of dollars—and again indispensable to advancing the interests of the state. The rise of such an industry is the result of growing instability and the unfettered advances of neoliberal policy-making in the role of government; in this sense, instability around the world has created favourable conditions—including increased demand—for security services, and private enterprises have exploited this. This drive for profit, in turn, represents a potential–and serious—risk to a liberal order purportedly founded on the pursuit of cooperation and peace, and not profit. Private military actors have made headlines around the world and set foot in many battlefields across the world, but are they agents of peace or catalysts for war?