The following correction was printed in the Guardian's Corrections and clarifications column, Monday April 2 2007
In the obituary below, we said Ada Maddocks was, "from 1977 until her retirement in 1992 ... national health officer for Nalgo (the National Association of Local Government Officers). Nalgo had become the National and Local Government Officers Association in 1952.
Ada Maddocks, who has died aged 79, was one of the leading women trade unionists of her day. From 1977 until her retirement in 1992, she was national health officer for Nalgo (the National Association of Local Government Officers), which is now part of Unison. She served on the TUC general council from 1977 until 1991, and in 1990 became only the fifth woman to hold the office of president. Her time on the TUC coincided both with a growth in the prominence of women in the trade union movement and the unions' battle against their most formidable woman opponent, Margaret Thatcher.
The bitter ambulance workers' dispute of 1989-90 occurred during Ada's year as TUC president and she gave unstinting support to all union members involved. She went to London's Smithfield market one cold winter's morning, long before dawn, to win the meat porters' support for the ambulance workers. They even let her stand on one of their barrows - an honour previously given only to the Queen Mother.
Ada was born in Felixstowe, Suffolk, and educated at Walthamstow county high school. She spent some of her childhood out of London as a wartime evacuee. After school, she started work as a laboratory assistant in the Co-operative Wholesale Society, and went on to join the Women's Co-operative Guild and the Co-operative Union in London.
She joined the staff of Nalgo in 1961 as a secretary in the electricity section and moved to the health section in 1966, becoming a negotiating officer. Ten years later, she became the national officer responsible for the health service, and then staff side joint secretary of the general Whitley council. When she joined the TUC, she was one of just two women (the other being Marie Patterson, of the T&G) elected in the seats traditionally reserved for women to ensure that the council was not an all-male club. By the time she left, she was one of 15 women on the 50-member body, and the slogan that "a woman's place was in her union" was one with which few trade unionists would disagree.
Her many friends and former colleagues remember Ada as a woman whose feet were firmly on the ground - she never let high office affect her judgment or the way she dealt with people. Many junior staff, and especially younger women in Nalgo, benefited from her friendship and encouragement, and went on to gain the promotion she was sure they would get. In 1982 she was awarded an OBE.
In retirement, Ada remained active in her local community. She was the chair of Redbridge Voices of Experience, which helped to produce the report Foundation for Change (2005), a health and social care strategy for older people and their carers in Redbridge, and was an active supporter of Age Concern.
She never married but enjoyed a rich family life with her siblings and their children. She is survived by her sister Margaret, brother Sam, their children and the children of her deceased sisters, Jesse and Irene.
· Ada Maddocks, trade unionist, born September 22 1927; died March 7 2007
