Hôtel d'Asséat was built in the 16th century over two phases by a wealthy dye plant merchant, designed by the architects Nicolas and Dominique Bachelier. This monument changed along with its use: accommodation, barrel making, the Académie des Jeux Floraux and then in the 1990s it became the Bemberg Foundation. It is home to works gathered by a collector with a specific and eclectic taste. This includes Dutch primitive art, Italian bronzes, English oils and other Pierre Bonnard works. Such a specific context required a specific approach. Firstly, carefully respecting the older elements; then working freely with new or reconstructed zones; finally maintaining a tone so the museum is largely coherent. In all cases, we avoided the museum outdoing the architecture, and vice versa. On the contrary, the goal was to design spaces where the works and architecture go hand in hand. Significant work was carried out in terms of general restoration, refurbishing the flooring and initial spaces, arranging the exhibition rooms, the new staircases and offices, as well as an extension to house the archives, the meeting rooms, a car park and the plant rooms in the basement. The architectural research focused on respecting the 16th century building and the main contributions of the 18th and 19th centuries.