In the 1980s, Gowing served as a trustee of the Science Museum, London, and the Imperial War Museum but, remembering her own childhood, she resigned from the latter in protest at the introduction of entry fees. She was also a trustee of the National Portrait Gallery from 1978 to 1992. She began suffering from what was most likely Alzheimer's disease, and retired from Oxford in 1986, two years before the official retirement age. Although she had worked in the Civil Service and Academia for 45 years, only 27 of them counted, so she was not eligible for a full pension; her son Nik supported her. She died at Kingston Hospital in Kingston upon Thames on 7 November 1998. An archive of her papers is held by the Museum of the History of Science in Oxford, presented by her in 1991, with additions on her death.