For much of the twentieth century, a chasm divided the disciplines of international relations and international law, with relatively little communication and even less mutual comprehension. In particular, this period saw the increasing exclusion of international law from the study of international relations, with key texts removed from reading lists. Perhaps the most obvious and significant reason for this exclusion was the dominance of the realist, and later, neorealist schools of thought in international relations. This phenomenon was certainly most notable in the United States, where the dominance of realism was most extensive. However, in recent decades, a rapprochement between the two disciplines has been attempted, led in the first instance largely by international lawyers. Despite significant efforts at bridging the gap, however, this article argues that a genuine dialogue has yet to emerge. Using insights from debates in and across each discipline about appropriate responses to mass atrocities, this article offers suggestions for creating such a dialogue.