This chapter explores how sociological methods, concepts, and theories have been engaged to study international peacebuilding. Sociology is used in three ways to study peacebuilding: as general ontological understanding of the research object as a “society” in which policymakers can intervene in order to achieve specific policy goals; as a set of observation methods; and as a reference in social theory and philosophy that allows criticizing peacebuilding’s configurations of power and inequality. Given their substantially different epistemologies, these ways draw a very uneven image of what that society actually is, how it “works,” and how it affects or is affected by peacebuilding.