Mary Wright was born in 1903 in Sydney, New South Wales. In 1919 she worked in a chocolate factory while living with her sister in Glebe and at age 17 she married John Lamm and started a family. She later married trade unionist Tom Wright. In 1926 she became involved with the Militant Women’s Group, based at the Trades Hall. The group was led by Hettie Weitzel and included Annie Isaacs, Clarice Irwin, Edna Nelson, Jean Thompson and Joy Barrington. As part of the group Mary Wright gave support to the Timber Workers in Sydney during the lockout in 1929 and in that year she joined the Communist Party of Australia. In 1930 the Militant Women’s Group dissolved. She was a founder of the International Women’s Day celebrations in Sydney and in 1936 became President of the first Sydney IWD Committee. She was involved in the formation of the Council of Action for Equal Pay in 1937 and became a State Council member of the United Associations of Women, taking part in drawing up the Women’s Charter of equal rights. She was a member of the New Housewives’ Association and a member of its successor, the Union of Australian Women when it was formed in 1950. In 1953 Mary and Tom Wright moved to Bankstown, where Mary became President of the Bankstown Branch of the UAW. Mary resigned from the CPA with Tom Wright in 1971 and joined the new Socialist Party of Australia.

Thomas (Tom) Wright was born in Scotland and emigrated to Australia about 1913 and was apprenticed in the sheet metal working trade at the age of fourteen. Wright joined the Sheet Metal Workers' Union in 1921 and in 1924 was appointed to the New South Wales Branch Executive of the Sheet Metal Workers' Union. He was the NSW Branch Secretary from 1936-1972, and was Federal President of the Union from 1940-1972. Wright pioneered amalgamations of the SMWU with the Jewellers' & Stove Makers' Unions in the 1930s and 1940s and contributed to the formation of the Amalgamated Metal Workers' Union. At the time of his retirement in 1972 he was the NSW State President and National Vice-President of the Amalgamated Metal Workers' Union.

Wright was a promoter of the ACTU in 1926-1927 and was the Sheet Metal Workers' Unions' delegate from 1938 to 1972, serving on the ACTU Executive for many years and on its Shipbuilding Sub-Committee from 1946-1963. He was actively involved on the Executive of the NSW Labor Council from the 1920s until his retirement in 1972. He was a member of the NSW Labor Council delegation which travelled to China and the Soviet Union in 1927. In 1943, Wright helped found the Metal Trades Federation on which he was a Sheet Metal Workers' Union delegate. He visited the Soviet Union again in 1952 and 1969, China in 1952, and in 1963 visited Cuba after the Batista regime was defeated.

Tom Wright and his wife, Mary, played a substantial part in the long campaign to achieve equal pay for women and were active in campaigns on Aboriginal rights.

The union was originally registered as the Amalgamated Tinsmiths' Sheet Metal Workers' Cannister Makers' Gas Meter Makers' & Assistants' Union in 1911 and comprised of unions that had operated since 1881. From 1913 its name changed to the Sheet Metal Working Industrial Union of Australia. In 1945 the union changed its name to the Sheet Metal Working Agricultural Implement & Stove Making Industrial Union of Australia to reflect growing membership from members of the Federated Agricultural Implement & Stovemakers' Porcelain Enamellers' & Ironworkers' Association of Australia. It was deregistered in 1972 and joined the Amalgamated Engineering Union to form the Amalgamated Metal Workers' Union in 1973.