In this study, we intend to understand the relationship between Brazil and Uruguay at the beginning of this century. We will start talking a little about the history of Uruguay and the aspects of its approximation to Brazil. We will approach the commercial relations between these two neighboring countries and the regional integration projects, talking about the FOCEM-MERCOSUR and the IIRSA-COSIPLAN-UNASUR at the length, focusing on Brazil-Uruguay relationships. After talking about the Brazilian and Uruguayan participations in these initiatives, we take interest in analyzing the relationships between the two countries in the GAN fields. Established in 2012, the High-Level Group Brazil-Uruguay (GAN) is meaningful to the biggest recent approach between them. The present research will comprise the integration carried out on the energy areas and other infrastructure work, such as the recovery of the railroads, waterways, bridges and roads with the challenge of surpassing the transportation difficulty on the borders. What matters, above all, is to highlight initiatives in the energy area like the Artilleros Wind Park in Uruguay, whose structure is mostly sponsored by Brazil, inserted in the dissemination strategy for renewable energy. It is also intended to explain the charges against the Brazilian expansionism through the projects and work designed to improve the bilateral relationship with Uruguay, which would be considered imperialist, and we may ponder on the subject defending that the process is complex depending on the negotiations between the involved countries.