He sought closer contact with the industry, including Thonet. In Berlin, he settled in as an architect and mainly worked in the interior design segment. In 1929, the company Standard-Möbel, which Breuer co-founded in 1927 and where produced his first tubular steel furniture, was acquired by Thonet. Breuer then worked for Thonet for several years. In the Thonet 1930/31 card catalogue, a comprehensive tubular steel collection, decisively influenced by Breuer, reveals an impressive range of work.
Via Budapest (1933) and London (1935), where he worked as an architect, Marcel Breuer moved to America in 1937. During this period, he developed plywood and aluminium furniture. With help from Walter Gropius, he became a lecturer and later on a professor of architecture at Harvard University in Cambridge, Massachusetts. Breuer ran a joint architecture office together with Gropius and, starting in 1941, he began working on his own, moving the office to New York in 1946. Among his most famous designs are the Whitney Museum of American Art in New York (1966, reopened as “The Met Breuer” in 2016), and the UNESCO headquarters in Paris (1958, with Bernard Zehrfuss and Pier Luigi Nervi). Breuer is considered one of the key characters in the history of architecture and design.