Focusing on intrastate conflicts in which third parties have played prominent roles, Hampson argues that durable settlements depend on sustained third-party engagement not only during the negotiation phase but throughout the implementation process.

Although the book explores the roles that other factors - such as regional and systemic power relationships, the terms of the settlement itself, and the role of "ripeness" - play in the success or failure of these peace settlements, it concludes that success hinges more on what third parties do and do not do.

In a crisp and engaging style, Hampson provides detailed yet succinct accounts of five justly renowned cases (Cyprus, Namibia, Angola, El Salvador, and Cambodia), explores the interplay of key variables, and describes rationales for action and lessons about how best to act.