How have power dynamics in the Americas influenced the trajectory of regional integration? This chapter draws upon theoretical conceptions of hegemony to better understand the regional project in Latin America. Building on contributions from the wider IR literature as well as the Latin American literature, I argue that a developed region requires a hegemon with a capacity and willingness to lead, along with a shared vision for the region. I demonstrate that in the Americas, the US embodied only the first of these qualities. This opened up the political space for a rising power to assume a hegemonic role in Latin America. I argue that Brazil has pursued regional integration as a way to limit US influence, but this project has been hindered by Brazil’s failure to act as a regional hegemon. First, Brazil’s potential capacity to shape the region has been limited by the US’s clear capacity to do so. Second, Brazil’s inconsistent willingness to provide leadership goods has prevented the achievement of deep integration. Finally, Brazil has only at times promoted a vision that was shared among its neighbors. The smaller states’ decisions to consent to or challenge Brazil’s vision is an important determinant of resulting regional institutions. Through my emphasis on the role of the global hegemon, regional powers, and small states in the creation of regions, I provide a rich understanding of the way that power—and lack thereof—has contributed to the relative shallowness of regionalization in Latin America.