This thesis explores the relationship between a current trend towards extreme privatization of urban areas and de-democratization under neoliberalism in the Brazilian context. This is done through two theoretical axes and an instrumental case study. The first theoretical axis is developed on the social production of urban space and social imaginaries; and the second, on neoliberalism and the crisis of democracy. The case study chosen was the 'first private neighborhood in Porto Alegre', Golden Lake, owned by Multiplan. The central argument is that, as part of an anti-democratic neoliberal political project, a radical form of urbanization is emerging, characterized by an enormous volume of socio-spatial privatization that imagines territories that are increasingly autonomous and unaccountable in relation to their external world. I call this emerging phenomenon 'Private Semi-Autonomous Territories' (PST). As a backdrop, I explore the relationship between society ideations and urban imaginaries, departing from Lefebvrian theory that urban space, from its conception, is imminently political.