By examining Nairobi’s and Madrid’s approaches to urban violence management, our applied research project sought to understand whether city diplomacy can facilitate multi-level, integrated policy approaches to urban violence. Now, this final report aims to provide researchers and practitioners alike with reliable evidence and viable pathways through which city diplomacy's potential as an innovative governance tool can catalyse a shift from policies passively managing urban violence to policies actively pursuing citizen security, a key component of the wider Sustainable Development framework.