The purpose of this article is to give an overview of current understandings of the various roles of business actors in armed conflict. It traces the expanding discussion of business and conflict in today’s civil wars, and the discussion’s importance to humanitarian, human rights, corporate and peacebuilding policymakers. It shows how the humanitarian understanding of business roles in conflict has progressed beyond some simple and largely negative stereotypes about business in war to become more sophisticated. The article then looks at the significant diversity of business actors, which can determine their experience of armed conflict. It is suggested that there are six potential roles of business in armed conflict – that of victim, perpetrator, supplier, humanitarian actor, peacebuilder, and conflict preventer. Finally, the article recommends a range of ways to improve humanitarian policy so that humanitarian actors engage with business more actively and appropriately on law, business relief, and business continuity.