Political yard signs are one of the most conspicuous features of American political campaigns, yet they have received little attention as a form of political communication or participation. In a climate in which the American public is highly polarized, these symbols are more than simple campaign tools—they are literal markers of partisan identity. As public cues that push into private life, they affect individuals and their neighborhoods, coloring perceptions of social spaces and impacting social networks. In Politics on Display we answer a series of questions about this familiar feature of electoral politics: Why do people put their preferences out there for the world to see? Do neighborhoods become political battlegrounds? And what are the consequences of displaying yard signs in these spaces where we spend most of our time? We answer these questions with an innovative research design, documenting political life in neighborhoods with complementary data sources: street-level observation of the placement of signs and neighborhood-specific survey research that delves into the attitudes, behavior, and social networks of residents. Integrating these data into a geo-database that also includes demographic and election data—and supplementing these data with nationally representative studies—we bring together insights from political communication, political psychology, and political geography. Against a backdrop of today’s political environment of conflict and division, we advance a new understanding of how citizens experience campaigns, why many still insist on airing their views in public, and what happens when social spaces become political spaces.