A dominant view within the field of international mediation is that the most effective type of third party to resolve civil wars is a high-leverage, manipulative power broker that can provide sticks and carrots in order to persuade the conflict parties to make peace.¹ This dominant view, which is based on a materialist logic, overlooks the role of ideational factors. In this chapter, I argue against the dominant materialist view of mediation success by illustrating that ideational factors matter in peace processes. More specifically, I show how a preference among the Government of Sudan (GoS) and the Sudan People’s Liberation