Ruth Chang is the Professor and Chair of Jurisprudence at the University of Oxford, a Professorial Fellow of University College, Oxford, and an American professor of philosophy. She is known for her research on the incommensurability of values and on practical reason and normativity. She is also widely known for her work on decision-making and is lecturer or consultant on choice at institutions ranging from video-gaming to pharmaceuticals, the U.S. Navy, World Bank, and CIA.