Hugh Ralston Crawford (1876–1954), practiced both as an engineer and architect in Australia and the United States in the first half of the 20th century.

[1] Crawford held the Australian patent rights for the Turner Mushroom flat slab system.

[citation needed] Crawford was granted an Australian patent in 1907 for a monolithic reinforced concrete cavity wall,[3] and built a number of Melbourne houses on this system.

[citation needed] From 1906 to 1914 Crawford conducted a private practice in Melbourne specialising in steel and reinforced concrete building.

From 1914 to 1919 he was employed by the John S. Metcalf Company Limited of Chicago-Montreal, Canada to construct bulk handling wheat silos for the New South Wales Government in Australia.