The system of EU Own Resources undergoes disruptive changes. The EU finalized a new Multiannual Financial Framework, decided on huge extra spending under the paramount Next Generation EU program and took loans. These changes have been accompanied by large-scale ECB and ESCB programs. While some observers prefer a more traditional, thus more reluctant financial framework, others dream of a Hamiltonian moment or debate about the introduction of a genuine European tax. Next to political and economic uncertainties, each of these steps triggers intri- cate legal questions. These questions are analyzed in this book. Thorough papers by Martin Nettesheim and Edoardo Traversa as well as further clear-cut statements by prominent experts contribute to a lively debate on the financial future of Europe.