This book argues that neutrality endures as a key concept of the law of armed conflict. The interaction between belligerent and nonbelligerent States continues to require legal regulation, as demonstrated by a number of recent conflicts, including the Iraq War of 2003 and the Mavi Marmara incident of 2010. By detailing the rights and duties of neutral states and demonstrating how the rules of neutrality continue to apply in modern day conflicts, this restatement of law of neutrality will be a useful guide to legal academics working on the law of armed conflict, the law on the use of force, and the history of international law, as well as for government and military lawyers seeking comprehensive guidance in this difficult area of the law.