Review of the hardback: '... a wonderful contribution to the discussion of and the verification of customary international humanitarian law. ... The book is recommended to practitioners, such as legal advisors to the armed forces and to peace operations and staff of the ICRC, academics working in the area of international humanitarian law, and everyone who is interested in the debate about (customary) international humanitarian law. As the ICRC Study is the basis for the discussion in this publication, the reader should have some basic knowledge about international humanitarian law and the ICRC Study, although the book is well readable because of its understandable writing and numerous examples and the authors illustrate some of the fundamental legal aspects to the reader by also extracting and explaining the profound questions.' The Military Law and the Law of War Review '... the volume is useful reading for students of international humanitarian law and practitioners alike.' Netherlands International Law Review