In July of 1963, Breuer agreed to design a new home for the Whitney Museum of American Art at the corner of Madison Avenue and 75th Street. The building with its stepped façade, wider at the top than at the base, became Breuer’s most recognizable work. The concrete building was sheathed in light gray granite and featured seven angled trapezoidal windows seemingly scattered across the south and east facades in a random manner. The visitor entered the building by crossing a concrete bridge over a sunken sculpture garden and passing under a cantilevered concrete canopy. The basement and first floor facades on Madison Avenue were fronted in glass. The open-plan galleries were uninterrupted by vertical supports; a gridded precast concrete ceiling featured adjustable track lighting and channels for partitions that could be used to subdivide the galleries. Breuer located administrative offices and a library on the top two floors where glass walls opened out to terraces fronted by parapets. The Whitney Museum combined the sculptural concrete tendencies of his later Breuer’s later career with the inverted stepped façade of the Elberfeld Hospital (1929) or the shopping center from the Garden City of the Future (1936). Breuer collaborated with his associate Hamilton Smith in producing the design for the museum, which opened to the public in 1966. Michael Irving served as consulting architect.