The ‘frontier’ is central to a new wave of development scholarship, but the broad deployment of the concept has blurred several key dimensions of frontier development. We focus on the Brazilian Amazon to synthesize classical frontier theory and emerging perspectives with special attention to the role of governance in frontier development. Since 2004, primary deforestation in the Brazilian Amazon has declined over 70 percent while agricultural production in the region has increased. Contrary to narratives that view this transition as the result of ‘frontier governance’ – i.e., the imposition of order on a pre-existing frontier – we propose the concept of a ‘governance frontier,’ which recognizes the role of politics in constructing and transforming frontier spaces. This concept politicizes economic accounts of frontier development and spatializes abstract notions of governance. We employ a ‘follow the policy’ methodology to trace the evolution of a governance frontier in the eastern Brazilian Amazon, drawing on original fieldwork across four Amazonian municipalities and inside an environmental non-governmental organization. We show that a key feature of the Amazonian governance frontier has been a distinct geographical configuration of ‘model municipalities’ that function as nodes of policy experimentation, legitimation, and transfer. Our findings support an integration of frontier theory and governance theory in a place-based, political geography approach to regional political-economic transformation, which demands greater attention to the political dimensions of frontiers and to the spatial dimensions of governance. © 2018 Elsevier Ltd