This chapter introduces the concept of affective citizenship in an effort to expand discussions on the nexus of affect, power, and institutions. Citizenship is one of the most fundamental political institutions, whose affective and emotional dimensions have been largely neglected in conventional scholarship. Building on earlier feminist, queer, and postcolonial critiques of citizenship, the emerging literature on affective citizenship analyses the governance through and of affects by exploring the policies, discourses, and institutional practices of states; however, it also attends to acts of affective citizenship, such as resistance or compliance by citizens and non-citizens alike. With the concept of affective citizenship, we can decipher how mechanisms of exclusion and inclusion proceed through the affective registers of citizenship. Given the persistence of institutional racism and problematization of migration, belonging, and identity in contemporary societies, an understanding of citizenship as an affective institution is critical for a comprehensive analysis of political boundary-making in plural societies.