Glen Francis Newey (30 May 1961 – 30 September 2017) was a political philosopher, last acting as a Professor of Practical Philosophy at the University of Leiden. He previously taught in Brussels at the Université Libre de Bruxelles and until 2011 was Professor in the School of Politics, International Relations & Philosophy at Keele University, Staffordshire, England. He was a prominent member of the "Realist" school of political philosophers which also includes such figures as Bernard Williams, John N. Gray, and Raymond Geuss. Newey also wrote extensively about toleration, casting doubt on whether it remains a coherent political ideal in modern liberal-democratic societies.