Sydney. In 1938–1939, he formed a brief design partnership with fellow-West Australian, John Oldham (Oldham & Baldwinson) to design a workers' housing project near Coomaditchy Lagoon, Port Kembla, New South Wales. In 1938, Baldwinson had his first solo commission, Collins House at Palm Beach. Baldwinson designed a red-stained weatherboard house on a sandstone plinth comprising an external stair ramp, two bedrooms, upper-level verandah and "playroom" on the lower level. The house received considerable media attention. Before the 1939–45 War disrupted his career, Baldwinson was on the organising committee for the formation of the Australian Modern Architecture Research Society (MARS) and Australia's first industrial design organization, the "Design and Industries Association of Australia" (DIAA.) During the 1939–45 War, Baldwinson worked for the Commonwealth Aircraft Factory designing and constructing buildings engaged in the manufacture of aircraft. By 1943, he had been promoted Chief Architect of the Beaufort Division, Department of Aircraft Production (DAP). Baldwinson later developed an all-steel pre-fabricated "Beaufort" house for DAP post-war sale to the Victorian Housing Commission in 1946. This was Australia's first fully factory-manufactured prefabricated steel house. In 1946 Baldwinson returned to Sydney and formed a partnership with Melbourne engineer, Eric Gibson. As Gibson and Baldwinson, Gibson managed the office in Melbourne and Baldwinson supervised the Sydney office. In this partnership Baldwinson produced his best residential designs for a number of Sydney's Contemporary Artists Society (CAS) members. These avant-garde clients included Alistair Morrison, William Dobell, Harold Clay, Geoff and Dahl Collings, James Andriesse, Max Dupain and Elaine Haxton. In 1950 he concluded his partnership and applied for a lectureship at Sydney University. By 1952, he was a Senior Lecturer in the architecture faculty. In 1953, Baldwinson formed a partnership with Charles Vernon Sylvester-Booth; in 1956 Charles Peters joined the firm to form Baldwinson, Booth and Peters. The partnership lasted until 1958 with Baldwinson concentrating on residential designs, which he favoured, while Booth and Peters pursued commercial work. One of their designs, Hotel Belmont, near Newcastle won the NSW RAIA Sulman Award in 1956. During this partnership, Baldwinson also designed the Mandl House, Wahroonga (1953) and the Simpson-Lee House, Wahroonga (1957). He also designed and built his own residence at 79 Carlotta Street, Greenwich (1954) funded by his teacher's salary. The Carlotta Street house is the most precise essay on Baldwinson's restrained modernist philosophy. Baldwinson's palette of materials was consistent throughout his practice: bagged brick, weatherboard or vertical tongue-and-groove