The international law of occupation is the body of law, under international humanitarian law, that regulates the actions of states—and possibly other actors such as international organizations—that gain effective control over territory during armed conflict. The law of occupation seeks to balance several interests, which are often in tension with one another. Its most fundamental principle is that occupation does not confer sovereignty, and that the powers of the occupant are limited. The occupant is viewed as a temporary trustee, empowered only to maintain public order and safety in the territory, including that of its own forces. The law of occupation seeks to ensure that the occupant respects the rights of the absent sovereign; respects and ensures the individual rights of the local population; as well as their right to self-determination. This book seeks to provide an entry point for those seeking to familiarize themselves with the topic, by elaborating on general principles and key rules. It explores the tensions and dilemmas which characterize the modern law of occupation, while highlighting, when needed, interpretations which best conform with the law’s object and purpose. All in all, this book aims to guide relevant actors when seeking to assess or to challenge state actions in occupied territories.