Brendan O’Leary is an Irish, European Union, and US citizen, and since 2003 the Lauder Professor of Political Science at the University of Pennsylvania. He is the author, co-author, and co-editor of twenty eight books and collections, and the author or co-author of hundreds of articles or chapters in peer-reviewed journals, university presses, encyclopedia articles, and other forms of publication, including op-eds. His latest production is a three-volume study called A Treatise on Northern Ireland, published by Oxford University Press, which was positively reviewed in the Dublin Review of Books, the Irish News, and the Irish Times, and won the 2020 James S Donnelly Sr Prize of the ACIS for the best book in History and Social Science. In 2018 he co-authored a research report, Northern Ireland and the UK’s Exit from the EU: What Do People Think? Evidence from Two Investigations: A Survey and a Deliberative Forum (PI: Garry, J., McNicholl, K., O’Leary, B., & Pow, J., Belfast, Queen’s University Belfast, 2018) sponsored by the UK’s Economic and Research Council. He is currently researching the UK’s secession from the EU, and possible models of Irish re-unification.

Professor O’Leary is the inaugural winner of the Juan Linz prize of the International Political Science Association for contributions to the study of multinational societies, federalism and power-sharing, and in 2016 he was elected an honorary member of the Royal Irish Academy, principally because of his contributions to the field of power-sharing. In addition to his scholarly work, O’Leary has been a political and constitutional advisor to the United Nations, the European Union, the Kurdistan Regional Government of Iraq, the Governments of the UK and Ireland, and to the British Labour Party (before and during the Irish peace process).