The twenty-first century began with the 9/11 attacks against the U.S., which triggered the outbreak of horrifying wars against Afghanistan and Iraq as well as operations in other parts of the world by the U.S. and its allies against the terrorist groups and their members in the framework of the so-called “war against terrorism”. These operations have challenged international humanitarian law (“IHL”) from different angles. For example, the misconduct towards individuals detained in Guantanamo Bay and isolated targeted killings in contexts out of armed conflict have resulted in debates concerning the legitimacy of these incidents and the interplay between IHL and international human rights law (“IHRL”). Moreover, Russia's attack against Crimea, the ongoing armed conflicts in Yemen and Syria, the hostilities between Azerbaijan and Armenia, international and non-international armed hostilities between States and non-State armed groups, which took place in the first decade of the new millennium, as well as developments in the arms industry and military technology have demonstrated that the IHL rules and principles of IHL as enshrined in the 1949 Geneva Conventions and other international instruments, as well as customary international law, are still vitally important to appropriately balance between military necessity and humanitarian observations in the times of war.

As mentioned in its preface, The Oxford Guide to International Humanitarian Law (“Guide”) is a guide for professionals who are not necessarily IHL experts (p. v). This book, which consists of eighteen chapters written by well-known IHL specialists, covers a wide range of topics, including both the classical and contemporary ones. The book starts with a brilliant chapter on the history and sources of IHL. Chapters 2 and 3 provide the reader with a general overview of the concept and different types of armed conflict, and the temporal and geographical scope of IHL's applicability. The book then moves on to the subject of protection, and through its various chapters, discusses the ways that IHL protects persons and objects in armed conflict. Some other chapters of the Guide are dedicated to introducing the laws and treaties on the means and methods of warfare. Several IHL contemporary challenges such as detention and application of IHL and IHRL in counter-terrorism operations are also studied in the Guide. Yet, as the book is also intended to be used by policymakers, legislators, government officials, and non-governmental organisations, the editors included a chapter to discuss implementation of IHL, which sheds light on the different roles that States and international organizations have to play to increase the level of compliance with the rules. The Guide also contains a chapter written by the late Professor Robert Cryer on war crimes.

With an in-depth introduction to various issues, reference to the case studies, and the State practice and case-law of national and international tribunals, the book has provided the readers with a valuable Guide illustrating how the IHL applies in practice.