Katrina Forrester is the John L. Loeb Associate Professor of the Social Sciences in the Department of Government and Committee on Social Studies at Harvard University. She is a political theorist and historian with research interests in twentieth-century and contemporary social and political theory. She is particularly interested in the history of liberalism and the left in the postwar US and Britain; Marxism, feminism, and psychoanalysis; climate politics; and theories of work and capitalism.

Forrester's first book, In the Shadow of Justice: Postwar Liberalism and the Remaking of Political Philosophy (Princeton University Press, 2019) is a history of how political philosophy was transformed by postwar liberalism, John Rawls's A Theory of Justice, and the rise of liberal egalitarianism. In the Shadow of Justice received the Organization of American Historians’ Merle Curti Award, the Society for US Intellectual History’s Book Award, and the Montreal Political Theory Manuscript Workshop Award, was co-awarded the International Conference for the Study of Political Thought's David and Elaine Spitz Prize, and was shortlisted for the Royal Historical Society’s Gladstone Prize and the European Consortium for Political Research's Political Theory Prize. 

Forrester received her PhD from the University of Cambridge in 2013, held a research fellowship at St John's College, Cambridge in 2012-14, and a permanent lectureship at Queen Mary University of London until 2017. She held a Kluge Fellowship at the Library of Congress in 2019-20, and will deliver the Quentin Skinner Lecture at Cambridge in 2023. At Harvard, she is a Faculty Affiliate of Studies of Women, Gender and Sexualty, the Safra Center for Ethics, the Inequality in America Initiative, and the Harvard University Center for the Environment.