This report accompanies the United Nations University Centre for Policy Research’s 2022 publication Stress Testing the UN’s Regional Prevention Approaches. This project was designed to take stock of the UN’s approaches to regional prevention several years after the introduction of interconnected UN reforms, and assess how these reforms have translated into different prevention approaches in three regions: Latin America, the Sahel, and the Horn of Africa. The main report found that expectations, strategies, and capacities to implement the Secretary-General’s prevention agenda varied considerably across all three regions, and offered a range of cross-cutting lessons and recommendations for future regional strategy development. The authors identify three prevention models: (a) a ‘cascading model’ in the Sahel, where regional strategies are meant to shape national plans; (b) a ‘net model’ in the Horn, that aims not only to provide a platform for prevention actors to come together in a very broad and permeable configuration, but also encourages them to move in the direction of greater coherence; and (c) an ‘alliance model’ in Latin America built around coalitions that form on the basis of appeals between Resident Coordinators and regional actors for specific and specialist input and funding, taking into account locally-identified risks. This report argues that there could be broader application of all or parts of these models across other settings. Understanding their nuances will improve the design of future prevention strategies, identify opportunities for multi-stakeholder partnership, and support programming at the national and regional levels.