Social media is changing the business of representation and lawmaker reputation building, and this book uses the US Senate to illustrate the constituent-driven nature of political communication. I offer a critical analysis of senators’ communication on Twitter, the forces that shape it, and the agendas that result. Senators strategically communicate a political image that reflects their unique political persona. They have to decide what they want to be known for, crafting communications that prioritize legislation, constituent service, and party politics in ways that meet the interests of their constituencies and foster promising electoral returns. Senators’ communicated, public priorities—what is termed in this book as the rhetorical agenda—offer a necessary tool for understanding how senators link their carefully crafted public image with potential voters. The rhetorical agenda uses more than 180,000 lawmaker tweets to challenge what we know about representation, removing the institutional and political constraints on congressional communication and giving lawmakers a messaging platform where individual discretion is high, the relative costs are low, and someone is always watching.