The new technical platform of the Kremlin-Bicêtre hospital take place in a remarkable historical perimeter, and in a context of marked topography. Its realization with an optimized operational phasing guaranteeing medical activities continuity is also a critical issue for the establishment. Dialoguing with the existing site, the new building fits into the slope. Taking advantage of the topography to restore more than 50% of the project’s footprint in green spaces, its garden terrace, accessible on one level, offers a real public space for visitors and staff. Two simple volumes emerge and highlight the entrances: the double height volume marks the main entrance of the ambulatory circuit from the forecourt, and the welcoming pavilion doctors and personal, accessible on one level from the upper garden. The integration of the building is achieved by its materiality, which affirms the modernity and innovation of the medical project, by transparency and precision. The natural stone clading echoes with historic buildings of the Kremlin-Bicêtre hospital. The facade is smooth, noble and perennial.