This review concerns political preferences—what they are and where they come from. We begin by documenting the close relationship between processes of preference formation and change. Rather than suddenly appearing, most preferences emerge from interactions between individuals and their environment. This aspect of preference formation poses a concrete challenge: to uncover the mechanics of these interactions in important social contexts. We then describe political science research that meets this challenge. We find an expansive literature that clarifies how phenomena such as parties, campaigns, and the need to act strategically affect preferences. This work provides many widely applicable insights.