Long viewed as an example of effective multilateralism, UN peace operations are facing mounting challenges. Transformations in the landscape of conflict are outpacing their ability to respond. Rising expectations of peacekeeping have led to disenchantment with what they can deliver, while dis- and misinformation tactics undermine the efforts of the UN to make and build peace. As UN peace operations risk becoming another casualty of intensifying international tensions, great power rivalry, and the erosion of the rules and norms that govern international cooperation, we consider the future of UN peace operations. In the debate between a “pragmatic” and an “adaptive” approach to peacekeeping, we argue that a fundamental question is the ability of both alternatives to address three recurring issues that have shaped the effectiveness and legitimacy of peace operations: the mismatch between ambitious mandates and limited resources; the gap between the protection of civilians objective and its implementation in practice; and growing difficulties in honoring the principles of impartiality. We argue that policymakers and researchers should not lose sight of the fact that peacekeeping's legitimacy depends on its adherence to some version of host-state consent and some kind of restriction on when and how force is used. The expectation of civilian populations that the UN stands for protection also means that the UN must continue to safeguard some key norms associated with peacekeeping.