This course offers a theoretical introduction to collective decision making. The first part of the course surveys classic results in social choice theory. We address the extent to which a group of diverse individuals can have a coherent collective preference. The second part turns to models of electoral competition, political accountability, and political influence (such lobbying and special interests, agenda setting, and vote buying). The last part of the course focuses on (mis)information in collective processes. Do mass elections aggregate citizens' dispersed information? What are the electoral effects of media bias? Is political persuasion a concern? Pre-reqs: ECONOMICS 601 (620 strongly recommended).