Corporate actors are taking on an increasingly significant role in the prosecution of modern warfare. Traditionally, an analysis of the law applicable to corporate actors in armed conflict commences with inquiry into the law as it applies to mercenaries. As such, the rise of the private military industry invites a reconsideration of the conventional approach to mercenaries under international law. This article critically surveys the conventional law as it applies to mercenaries, and considers the extent to which corporate actors might meet the legal definitions of a “mercenary”. It demonstrates that even mercenaries receive protection under international humanitarian law.