Financialization and sustainable urban planning are now two major components of urban production and landscape change in Western cities. On the one hand, urban propertyand more specifically major urban projects or megaprojects such as, for example, business districts, airports, sports stadiums or even urban network infrastructures -is increasingly owned by financial actors. On the other hand, these urban megaprojects have a significant impact on the organization of urban functions and city planning, which lean increasingly towards the precepts of sustainable development.The purpose of this article is to demonstrate how the intervention of financial actors influences urban sustainability in the building of a megaproject. Within the framework of an institutionalist and territorial approach to the economy (Colletis-Wahl et al., 2008;Crevoisier, 2010), this article develops an analytical framework that allows us to grasp the relationships between finance and sustainability in the urban production process. To be more precise, this framework aims first to examine the way in which sustainability has been produced by the different actors involved in a real-life situation, and then to place these interactions in their institutional, spatial and temporal context. Over the course of the different phases of one project, the actors constructed formal and informal institutional arrangements (Hodgson, 2006), reflecting issues that are financial and at the