A growing number of states use private military and security companies (PMSCs) for a variety of tasks, which were traditionally fulfilled by soldiers. This book provides a comprehensive analysis of the law that applies to PMSCs active in situations of armed conflict, focusing on international humanitarian law. It examines the limits in international law on how states may use private actors, taking the debate beyond the question of whether PMSCs are mercenaries. The authors delve into issues such as how PMSCs are bound by humanitarian law, whether their staff are civilians or combatants, and how the use of force in self-defence relates to direct participation in hostilities, a key issue for an industry that operates by exploiting the right to use force in self-defence. Throughout, the authors identify how existing legal obligations, including under state and individual criminal responsibility should play a role in the regulation of the industry.

'… not merely contributes to the existing literature on PMSCs, but could even play a role in regulating PMSCs around the world. This well-researched work will appeal to academics, students, scholars, humanitarian and human rights activists in various disciplines, including international security, public international law, humanitarian and human rights studies.' Kai Chen, International Affairs
'[Lindsey Cameron and Vincent Chetail] have done a heroic job of imposing some analytic order on … seeming legal chaos, at least with respect to public international law. Bringing great rigor, depth, and clarity to the task, [they] provide a systematic overview of the multiple bodies of public international law that govern the contractors themselves and the states and others that employ them … [this book] is breathtaking both in its scope and attention to detail and will surely serve as a lasting and essential resource for anyone working in the field of privatized foreign affairs … Cameron and Chetail are to be lauded for their extraordinary efforts to clarify the international law framework to be applied to PMSCs …' Laura A. Dickinson, The American Journal of International Law

Lindsey Cameron is a Legal Adviser for the International Committee of the Red Cross. Prior to joining the ICRC, she worked as a researcher in the faculty of law at the University of Geneva. She has also worked for the UN High Commissioner for Refugees in the Balkans and at the Court of Appeal for Ontario in Canada. Vincent Chetail is Professor of Public International Law at the Graduate Institute of International and Development Studies, Geneva. He is also Director of the Global Migration Centre and formerly the Research Director of the Geneva Academy of International Humanitarian Law and Human Rights. His main field of interest relates to the various branches of international law applicable in times of armed conflicts.