Jason M. Roberts is a professor of political science at the University of North Carolina at Chapel Hill. His research focuses on legislative institutions, institutional development, and congressional elections. He is the author or coauthor of numerous books and articles on Congress, including Why Not Parties? (coedited with Nathan Moore and David Rohde; University of Chicago Press, 2008), Ambition, Competition, and Electoral Reform (with Jamie Carson; University of Michigan Press, 2013), and The American Congress (with Steven Smith and Ryan Vander Wielen; Cambridge University Press, 2015). Roberts received a Social Science Research Council Negotiating Agreement in Congress research grant in 2017–2018 for a project titled “Party Effectiveness in Congress.”