After its emergence in 2009, the Tea Party rapidly became a significant force in American politics. Yet, by 2014, multiple signs pointed to a significant decline in activism. What happened to the Tea Party? This chapter provides an overview of the Tea Party, its activities, and central actors, followed by a summary of our theoretical approach to understanding the movement. The chapter also details the main research questions and provides chapter summaries. The Tea Party is characterized as an insurgent social movement that was split across three main actors: elite conservative groups that facilitated the Tea Party’s emergence, grassroots activists who staged protests and founded local chapters, and Republican politicians who gave voice to the institutionalized faction of the movement.