The unsustainability of the globalized food system is a relevant debate. Despite the vast amount of literature on sustainable food systems, there is little research explaining how food system innovations can scale impact and influence systemic change. Moreover, not much literature considers the territorial context in which innovations take place, as a key factor in fostering transition. In this paper, we attempt to understand how territorial factors, such as actors and networks, influence sustainable food system transition. To achieve this goal, we built and applied an original methodology that was able to map the specific territorial context and dynamics. Considering a case study of 12 urban food system innovations in Montpellier (France), we reconstructed the relational context, in order to demonstrate the key role of embedded territorial dynamics in fostering sustainable transition. The application of our methodology produced about seven territorial conditions, which are defined by the differences between innovations, power relations and dynamics, the role of politics and the so-called “spaces of governance”. Each of these conditions plays a critical role in the transition to a sustainable food system.