In this essay, Iaddress some preliminary considerations surrounding different notions of “peace” and peacebuilding and the appropriate methodologies to study the same.I place emphasis on the adoption of a moral epistemology that is overtly value-oriented and normatively ambitious without being oblivious to the structural characteristics of collective political behavior that tend to privilege the self at the expense of the other, such as that used by the World Order Models Project (WOMP). Rather than relying on one standard definition of “cosmopolitanism,” I advocate for a pluralistic conception that acknowledges different cosmopolitanisms. I provide a framework for peacebuilding assessment that frames inquiry around different “horizons” of aspirations (feasibility, necessity, desperation, desire), and I lay out my version of cosmopolitanism, which centers on the importance of peacebuilding objectives that are necessary and desirable. In so doing, I compare my perspective toother paradigmatic perspectives, concluding that cosmopolitanismis concerned with reconciling unity with difference, through mutual understanding of otherness.