Santos, Luciano Alves dosBeutler, Nicole Vicenzi2024-03-042024-03-042020https://repositorio.uricer.edu.br/handle/35974/557The Proposed Constitutional Amendment n.º 45/2019, primarily intended to change the National Tax System, by replacing five taxes at the three federated levels - Union, States, Municipalities and the Federal District - by the Tax on Assets and Services, raised the debate about the need to modernize and simplify the collection method, as well as the handling of federative issues. That new tax follows the international model of Value Added Tax - VAT, and appears to be more effective and more transparent in the collection, benefits for public entities and taxpayers, simultaneously. However, with a single hoarding, the transfer to the states and municipalities reveals the fundamental tax difficulty among the federated entities, which currently have the possibility of assigning differentiated and personalized rates, according to their interests, based on the autonomy granted in the constitutional text, and that can be harmed in isolation with such a modification. From the detailed analysis of the provisions of the proposal regarding the transition from the current to the proposed format and the maintenance of autonomy for setting rates, it is understood that the federative problem is overcome by the implementation of the tax and the resulting modernization is beneficial to the national economy. For this, the deductive method was chosen, with analysis and discussion of doctrinal positions and deepening of legislative issues.pt-BRDireitoReforma tributáriaFederalismo tributárioTrabalho de Conclusão de Curso