The École Polytechnique , a renown french school, will teaching programs shared by the higher education and research establishments of École Polytechnique, Institut Mines-Télécom, AgroParisTech, ENSTA (École nationale supérieure de techniques avancées), ENSAE (École nationale de la statistique et de l'administration économique) and IOGS (Institut d'Optique). With its distinctive silhouette, the 10,000 m2 building allows itself to be invaded by the natural surroundings of the neighbouring linear park. A large area is home to light vegetation and a set of walkways and staircases that provide informal spaces for teachers, students and visitors to meet or work. These platforms, "spontaneous amphitheaters" and classrooms are united under one roof in a privileged relationship with nature. To instinctively identify the main areas and flows, we designed three mobiles distributed along the three main axes of the building. They are composed of a cable onto which branches of thermo-lacquered metal tubing are attached. These arborescences poetically indicate the program for each floor. A clever design of counterweights ensures balance. In this way, the mobiles interact with the minimalist architecture and the tree-like language of the planting. In continuation of this clean approach, we used ITC Avant Garde Gothic typography with different levels of boldness. The higher we go up the spaces, the thicker the typography becomes. A family of pictograms was custom-designed using a sans-serif typeface. Following the same gradation scheme as the typography, the pictograms thicken on the upper floors. In short, our approach to signage was to be minimalist and poetic, in the image of the architectural project. As a result, people no longer meet in corridors, but in living spaces, in the middle of a space bathed in soft light, with surprising and changing views. Its wide, transparent facade opens to the west. The building reads like an open space, revealing the activities taking place at its heart, and is intended as an architectural and academic emblem of the future district.