The wars of the 1990s confirm a basic finding from the study of civil war termination: "peacemaking is a risky business." The greatest source of risk comes from spoilers - leaders and parties who believe that peace emerging from negotiations threatens their power, worldview, and interests, and use violence to undermine attempts to achieve it. When spoilers succeed, the results are catastrophic. But not all spoilers do succeed.

The crucial difference between the success and failure of spoilers is the role played by international actors as custodians of peace. This study begins to develop a typological theory of spoiler management, providing a first step toward understanding the spoiler problem in peace processes and evaluating the appropriateness and effectiveness of different strategies of spoiler mangement.