Shaped by the changing nature of international conflict, the field of international conflict resolution evolved significantly throughout the latter years of the twentieth century and continues to be redefined. The end of the Cold War created space for a major transformation of the international conflict resolution field. This transformation was marked by three trends: (1) an expansion from a focus on superpower negotiating strategies to a wider peacebuilding agenda, (2) an increase in the role of nongovernmental actors as both disputants and third parties in international conflicts, and (3) a growing concern about human security in addition to state security, creating both tensions and opportunities for collaboration between governmental and nongovernmental bodies. This article presents a brief overview of each trend, as well as some concluding questions to frame the field's further development at this important juncture. © 2009 President and Fellows of Harvard College.