William Samuel (W.S.) Cox (1831–1895) was a pioneer of Thoroughbred racing in Australia.^[1] He opened his first venture, Kensington Park Racecourse, in 1874, which operated until 1882. He founded the Moonee Valley Racing Club in 1883,^[2] on land he leased the previous year.^[1] The Cox Plate, a prestigious Group 1 horse racing event, that has been held annually at the Moonee Valley Racecourse, Melbourne in October since 1922, is named after him.^[1]

Other members of Cox's family to contribute to Australian racing include his sons A. H. (Archie) Cox, who became club secretary; and W. S. Cox, Jr., a successful amateur jockey and trainer; the latter's son William Stanley Cox; and his son, William Murray Cox.^[1][2] The family, who have been involved in the administration of racing for nearly 120 years, were collectively inducted into the Australian Racing Hall of Fame en bloc in 2006.^[2]