Warington Smyth was called to the bar in 1899 and in 1900 was delegate for Siam to the Congres International, Paris Exhibition. In 1900, he was Hon Secretary for London of the National Committee for the organization of a Volunteer Naval reserve. In 1901 he went to South Africa where he was Secretary for Mines in the Transvaal from 1901 to 1910. He was also Member of Legislative and Executive Councils, Transvaal in 1906 and 1907 and a JP and Advocate of the Supreme Court of the Transvaal. He was also President of the Transvaal Cornish Association from 1907 to 1910, in which year he was awarded the Queen's South Africa medal. From 1910, he was Secretary for Mines and Industries in South Africa and Commissioner of Mines for Natal as well as Chief Inspector of Factories.