Landsberg studied with Gropius and Breuer at Harvard and worked for them in Cambridge. He left briefly to work for Skidmore, Owings and Merrill before returning to work for Breuer in New York. He worked on numerous projects such as the first Breuer House in New Canaan, Conn., the first Gagarin House, the Grosse Pointe Public Library, the Ferry Cooperative Dormitory and the House in the Museum Garden. He left Breuer’s employ in 1954 to open his own office.