This volume focuses on the concept of a necessary entity through an interlinking with two organizational principles - the principle of cooperation and the principle of hierarchy - which imply the notions of sovereignty, respect, and the ability to undertake joint administrative action in the European Union. The German concept of Europaischer Verwaltungsverbund is translated as European Composite Administration. After a general introduction to the concept of European Composite Administration, the book's contributions are divided into three parts. In the first section, various fields of European administrative law are analyzed, including: structural funds * European environmental law and the law on plant protection products * financial services and (more specifically) the law on insider dealing * European veterinary and food law * European aviation law * the law on police and customs cooperation * European product safety law * transnational water management * public access to documents. The second part focuses on acts and procedures in the European Composite Administration, such as: an in depth analysis of the Transnational Administrative Act * the general law of procedure of mutual administrative assistance in the European Union * an analysis of the administrative decision as a means of normative law making * the role of inspections as an instrument of implementation * an analysis of EC grant management. The book ends with essays on administrative structures and legal protection, including analyses of: the voidable decision as a form of legal protection * the system of legal protection and liability in EU law * the role of human rights in the transnational cooperation in criminal matters * the transnational ne bis in idem principle. The collection is the result of a continuous cooperation between legal scholars of Utrecht University and the Institute for German and European Administrative Law at Heidelberg University. In part, it was supported by the German and Dutch Research Foundations (the Deutsche Forschungsgemeinschaft (DFG) and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO).