A challenger to the continuing dominance of neorealism and neoliberal institutionalism in the study of international relations in the United States, constructivism is regarded with a great deal of skepticism by mainstream scholars.1 While the reasons for this reception are many, three central ones are the mainstream's miscasting of constructivism as necessarily postmodern and antipositivist; constructivism's own ambivalence about whether it can buy into mainstream social science methods without sacrificing its theoretical distinctiveness; and, related to this ambivalence, constructivism's failure to advance an alternative research program. In this article, I clarify constructivism's claims, outline the differences between "conventional" and "critical" constructivism, and suggest a research agenda that both provides alternative understandings of mainstream interna-