This open access book represents a multiyear exploration into identity-based mass violence (IBMV) within urban contexts. It explores the complexities of structural and acute violence in cities, drawing on local solutions rooted in the fields of urban violence prevention, atrocity prevention, and peacebuilding. The authors present a multidimensional approach that addresses sexual and gender-based violence, racial and ethnic violence, gang or group-based violence, state-perpetrated violence, political violence, violence against migrants, and others. The volume investigates the outsized influence of power in shaping how violence is understood and how prevention outcomes are evaluated. The chapters span scholarship, practical guidance, and lived experience of enduring and bearing witness to IBMV. This volume speaks directly to reform-minded partners and allies in policy and practice, as well as to funders and supporters. It provides a practical foundation for collaborative, prevention-focused action and policy opportunities.