Abstract The volume aims at the conceptualization and rationalization of the The ‘Legal Pluriverse’ Surrounding Multinational Military Operations. This term is used to describe the multiplicity of rules that apply to and regulate contemporary multinational missions and the diversity of actors involved. The book intends to systematically compile and take stock of the various legal regimes which make up this pluriverse, to assess how these rules interact, and to expose norm conflicts, areas of legal uncertainty, or protective loopholes. Taken together, the book’s individual contributions identify and evaluate approaches to better streamline the different applicable legal frameworks with a view to enhancing cooperation and thereby to ensure the long-term success of multinational military operations.