The composition of UN peacekeeping missions

We explore the role of mission composition as a potential factor influencing the outcomes of UN peacekeeping operations. We focus on three important dimensions of composition: who the peacekeepers are, how they are combined, and whom they interact with. First, using data visualizations, we show who is keeping the peace and how the composition of UN missions have fundamentally changed since 1991. Second, we point out how studying peace operations' composition urges us to partially revise the mechanisms that can affect peacekeeping effectiveness. We introduce four mechanisms: resolve commitment; informative trust; informative communicability; skilled persuasion. Third, we review recent empirical findings on UN mission composition and its consequences. We conclude this chapter by outlining policy implications and a research agenda bringing missions' composition to the fore.