Modern military operations include combat in armed conflict, law enforcement activities, and peace support operations. In this increasingly complex environment, it is imperative that armed forces incorporate international humanitarian law and relevant human rights law into the planning and execution of military operations. This Handbook highlights the most important elements of the international law governing military operations and places them in a practical, operational context. It is intended to facilitate the law’s application by all armed forces and to assist commanders in their task of incorporating that law into military strategy, operations and tactics. It is therefore a fitting successor to the original Handbook on the Law of War for Armed Forces compiled by Frédéric de Mulinen and first published by the ICRC over 30 years ago.