Deveson was also an active lobbyist for the rights of women, children and the disabled. Following the diagnosis of her son Jonathan with schizophrenia and his death from a drug overdose, she helped to start the Schizophrenia Fellowship of NSW in 1985. In 1986 she worked with Dr Margaret Leggatt to launch the national body Schizophrenia Australia Foundation, now named SANE Australia. She was also a member of the Royal Commission into Human Relationships (1974–77), NSW Medical Tribunal (1999–2010), Expert Advisory Group on Drugs and Alcohol (1999–2007) and the NSW Mental Health Tribunal (2002–07).