 He became a full-time official in 1951, and in 1956 was elected as General Secretary of the union, also being elected to the General Council of the Trades Union Congress.Smith joined the National Economic Development Council and was a part-time director of the British Overseas Airways Corporation.He stood down from his trade union post in 1966, to become Director of Labour Relations at the British Steel Corporation, in which role he frequently came into conflict with the steel workers' trade unions.