The city of Nancy (France) launched a Living Lab approach for the redevelopment of its eco-district. The first step of this project focuses on ideas exploration with the organization of participative workshops grouping citizens, technicians and politicians around the same table. The Environment and Methodology of Acceleration space or EMA space proposes ten theoretical functions adapted to realize collaborative workshops. The operational implementation of the EMA space functions is analysed according to two Living Labs characteristics-uses analysis and multidisciplinary collaborative work-and discussed. Organizers skills and political willingness are key aspects of the workshops success. The Lorraine Smart Cities Living Lab was designed to support public and private structures in their projects of high social and societal impact (mobility, city planning, self-directed learning, development of innovative economic activities, etc.) by providing tools, methods and multidisciplinary skills. It is made up of two entities: the university in charge of the scientific (ERPI laboratory) and operational part (NIT InoCite), and an incubator for innovative start-ups (Promotech). The aim of this paper is to analyse the construction of an environment adapted to ideas exploration within an urban Living Lab experimentation. The project concerns the redevelopment of the train station area in the city of Nancy (northeast part of France), done through workshops (ateliers) known as the "Ateliers de la Fabrique". La Fabrique is the place where the workshops are set and is located in the heart of the train station area. The Ateliers de la Fabrique follow a participative approach through the organization of multidisciplinary workshops composed by citizens, technicians and politicians involved in the evolution of this part of the city. The goal is to favour ideas co-construction instead of participating to a debate on ideas. This aspect was already worked by Dupont who defined the ten theoretical core functionalities of an Environment and Methodology of Acceleration space or EMA space (Dupont, 2009).