Summary

Behavioralism is a paradigm that became predominant in American social sciences from the 1950s until well into the 1970s. Although its reign did not last beyond the 1980s, it has transformed the fields of (American) political science and international relations (IR) so profoundly that it remains to this day an essential, albeit implicit, component of their identity. The article starts with the context in which behavioralism emerged, then engages the “Behavioral Revolution” in American political science and presents its main epistemic, ontological, and axiological tenets. It then moves more specifically to Behavioralism in IR, and to the terms of its “second debate.” The article concludes with an assessment of Behavioralism’s legacy.