The 2002 enactment of the first major reform of U.S. federal campaign-finance law in a quarter century featured a more substantial engagement of political scientists—through research, public advocacy, and expert testimony—than had been the case in the past. This essay reviews the evolution of research on campaign finance from the early twentieth century to the present, the intellectual tensions between the scholarly and reform communities, the conditions in the 1990s that promoted collaborationamong these groups, and the continuing disagreements over how best to manage the problems associated with money and politics—in the United States and in democracies around the world.He gratefully acknowledges the research assistance of Emily Bailard, a Brookings summer intern from Yale University, and Larissa Davis. Bruce Cain, Anthony Corrado, and Trevor Potter provided valuable commentary as discussants when a version of this paper was presented at the 2002 meeting of the American Political Science Association in Boston. Special thanks to Sarah Binder, Richard F. Fenno, Jr., Charles O. Jones, Sheilah Mann, Norman Ornstein, this journal's editors, and two anonymous referees for their helpful comments. The author would like to note that he alone is responsible for whatever errors of fact and judgment remain.