Wainwright was educated at the independent Mount School on Dalton Terrace (A59) in York, followed by St Anne's College at the University of Oxford, where she studied PPE. She graduated in 1970. She gained a BPhil in Sociology from St Antony's College, Oxford in 1973.
Until 1979, Wainwright was a research fellow at the Department of Sociology at Durham University. From 1979-81, she was a researcher at the Technology Department of the Open University. In 1982, she became Ken Livingstone's Deputy Chief Economic Advisor to the Greater London Council .
Wainwright is a Fellow of the international think tank for progressive politics, the Transnational Institute, Amsterdam; Senior Research Associate at the International Centre for Participation Studies at the Department for Peace Studies, University of Bradford, UK and previously research fellow at the Centre for the Study of Global Governance at the London School of Economics. She has also been a visiting Professor and Scholar at the University of California, Los Angeles; Havens Center, University of Wisconsin, Madison and Todai University, Tokyo.
She is a researcher and writer on the emergence of new forms of democratic accountability within parties, movements and the state. She has documented countless examples of resurgent democratic movements from Brazil to Britain and the lessons they provide for progressive politics.
Wainwright founded the Popular Planning Unit of the Greater London Council during the Thatcher years, and was convenor of the new economics working group of the Helsinki Citizens’ Assembly from 1989 to 1994.
Formerly on the editorial board of New Left Review, she was also on the National Council of the Catalyst think tank, the only such body on the Left in the UK which did not accept corporate sponsorship, a position was able to maintain thanks to sponsorship from the trade union movement.
She received an Honorary DLitt from the University of Huddersfield on 28 November 2007, with her brother Martin, for 'services to journalism'.
Hilary Wainwright has written for The Guardian, The Nation, New Statesman, Open Democracy, Carta, Il Manifesto and El Viejo Topo, as well as appearing as a commentator on the BBC.