While privatization is not a new concept for the US military, the public debate on military privatization is limited to legal, financial, and pragmatic concerns. A critical assessment of the ethical dimensions of military privatization in general is missing. More specifically, in light of the increased reliance upon armed contractors, it must be asked whether it is morally permissible for governments to employ them at all. To this end, this book explores four areas that highlight the ethical implications of using armed contractors: how armed contractors are distinct from soldiers and mercenaries; the commodification of force; the belligerent equality of combatants; and the impact of armed contractors on the professional military. While some take an absolutist position, wanting to bar the use of private military altogether, this book reveals how these absolutist arguments are problematic and highlights that there are circumstances where turning to private force may be the only option. Recognising that outsourcing force will continue, this book thus proposes some changes to account for the problems of commodification, belligerent equality, and the challenge to the military profession. This book will be of interest to students of private security, military studies, ethics, security studies, and IR in general.