Gary John Dorrien (born March 21, 1952) is an American social ethicist and theologian. He is the Reinhold Niebuhr Professor of Social Ethics at Union Theological Seminary in the City of New York and Professor of Religion at Columbia University, both in New York City, and the author of 18 books on ethics, social theory, philosophy, theology, politics, and intellectual history. Prior to joining the faculty at Union and Columbia in 2005, Dorrien taught at Kalamazoo College in Michigan, where he served as Parfet Distinguished Professor and as Dean of Stetson Chapel. An Episcopal priest, he has taught as the Paul E. Raither Distinguished Scholar at Trinity College in Hartford, Connecticut, the Horace De Y. Lentz Visiting Professor at Harvard Divinity School in Cambridge, Massachusetts, and the Lowell Visiting Professor at Boston University School of Theology. Dorrien is a member of the Democratic Socialists of America's Religion and Socialism Commission. Dorrien grew up in a working class, semi-rural area of middle-Michigan, Bay County, and in nearby Midland, Michigan. His parents, Jack and Virginia Dorrien, grew up in poor areas of Michigan's Upper Peninsula. Growing up, his family was nominally Catholic. Dorrien played multiple varsity sports at Midland High School and Alma College, graduating summa cum laude from Alma in 1974. He earned graduate degrees from Union Theological Seminary, Princeton Theological Seminary, and a Doctor of Philosophy (PhD) from Union Graduate School in 1989. He has been awarded honorary doctoral degrees from MacMurray College (DLitt, 2005), Trinity College (DD, 2010), Meadville Lombard Theological School (LHD, 2015), and Virginia Theological Seminary (DD, 2020). Dorrien won the American Library Association's Choice Award in 2009 for his book Social Ethics in the Making: Interpreting an American Tradition, which The Christian Century described as "magnificent, sprawling and monumental.