2022 as a Non-Executive Director of ASX listed Immutep (formerly Prima BioMed Ltd). Turnbull has a long-standing interest in cities and their planning, governance and management, as well as the importance of technological innovation to the national economy. In 1999, she published a book called Sydney: Biography of a City. She was an independent member of the Sydney Metropolitan Development Authority, which was charged with the urban renewal and revitalisation of several precincts in Sydney, including Redfern–Waterloo. She was an independent member of the Redfern–Waterloo Authority from its establishment in 2004 until its repeal in December 2011. She is a former board member of the Australian Technology Park, Redfern. From 2004 until 2011, Turnbull served as Deputy Chair of the Committee for Sydney, a think tank for Greater Sydney representing public, private and not-for-profit sectors and focused on the future of the metropolitan city, and chaired it from 2011 until 2015. Turnbull is a former deputy chair of the Council of Australian Governments (COAG) City Expert Advisory Panel (appointed July 2010), which reported to the COAG Reform Council. The Expert Panel was charged with preparing a report published on 1 March 2012, advising COAG Reform Council on whether metropolitan planning systems were consistent with agreed COAG criteria. Turnbull has also been active in the not-for-profit sector. She serves on boards of the Biennale of Sydney, the Redfern Foundation Limited and the Turnbull Foundation. She is the Patron of DICE Kids, an organisation created at Policy Hack in 2015 and Patron of the United States Studies Centre at the University of Sydney. She is also a board member of the NSW Cancer Institute. She has previously chaired the Sydney Children's Hospital Foundation, the Sydney Cancer Centre and the Sydney Festival Limited. From 2006–2010, she was a board member of Melbourne IT and before that a board member of WebCentral Limited. On 26 January 2011, Turnbull was appointed an Officer of the Order of Australia (AO) for her distinguished service to the community, particularly through philanthropic contributions to, and fundraising support for, a range of medical, social welfare, educational, youth and cultural organisations, to local government, and to business. In 2012, Turnbull was awarded an honorary Doctorate of Business by the University of NSW, and in 2016 was appointed Adjunct Professor at the Faculty of Built Environment, University of NSW. In 2017, she was awarded an honorary Doctorate of Letters from Western