The threat to human rights posed by non-state actors is of increasing concern. The author addresses the international obligations of belligerents, national liberation movements and insurgent entities, looks at the growing demands that such armed groups respect human rights norms and considers some of the options for holding private military companies accountable with regard to human rights abuses. The argument developed throughout this article is that all sorts of non-state actors are increasingly expected to comply with principles of international human rights law.