In this pioneering book, Louiza Odysseos argues that debates about ethnic conflict, human rights, and the viability of multicultural communities all revolve around the question of coexistence. Yet, issues of coexistence have not been adequately addressed by international relations. Instead of being regarded as a question, \u201ccoexistence\u201d is a term whose meaning is considered self-evident. The Subject of Coexistence traces the institutional neglect of coexistence to the ontological commitments of international relations as a modern social science predicated on conceptions of modern subjectivity. This reliance leads to the assumption that coexistence means little more than the social and political copresence of individuals, a premise that occludes the roles of otherness in the constitution of the self. Countering this reliance necessitates the examination of how existence itself is coexistential from the start. Odysseos opens up the possibility of a coexistential ontology, drawing on Martin Heidegger and his interlocutors, in which selfhood can be rethought beyond subjectivism, reinstating coexistence as a question for global politics-away from the restrictive discursive parameters of the modern subject. Louiza Odysseos is senior lecturer in international relations at the University of Sussex.