Partisanship is a dirty word in American politics. If there is one issue on which almost everyone in our divided country seems to agree, it’s the belief that the intense loyalty within the electorate toward Democrats and Republicans is the source of our democratic ills—division, dysfunction, distrust, and disinformation. The possibilities that responsible partisanship can offer were at the heart of an important intellectual tradition that flourished in the 1950s and 1960s, one which was institutionalized through a sweeping set of congressional reforms in the 1970s and 1980s. In Defense of Partisanship reimagines what partisanship might look like going forward from today. A new era of party-oriented reforms has the potential to pay respect to the deep differences that divide us while simultaneously creating a more functional path on which two responsible political parties compete to shape policy while still being able to govern.