Presenting a case study of enclavisation and violence in Karachi (Pakistan) as relational processes, this interdisciplinary project addresses key conceptual and empirical gaps in the scholarship on enclaves and enclaved urbanism. The project is presented in two parts. In the first part, I highlight that urban residential enclaves are presently under-theorised in the urban studies literature. Consequently, scholars and policymakers often problematically regard enclavisation as a response to increasing crime and violence in the city and not as a process that perpetuates urban violence. Engaging with relational theories of space, and using the concepts of assemblage and performativity, I re-theorise enclaves as relational and processual socio-material and socio-political assemblages best characterised through the arrangements through which space, security and circulation are governed in the city. In the second part of this project, I use this re-conceptualisation to review empirical evidence from three different types of residential enclaves in Karachi. First, I introduce my study sites by demonstrating how each residential enclave crystallises through differential multi-scalar relations between urban governance and political life. Next, I move on to show how Karachi’s enclaves are often performatively and discursively constructed, and are made apparent through patterns of circulation rather than physical form. By revealing the underlying tensions, contests and negotiations between variously positioned actors interacting within and between Karachi’s enclaves, I establish that enclaves are dynamic spaces. Moreover, in emphasising the ways in which processes of enclavisation shape urban socio-spatial relations and restructure wider relations of power and politics in the Pakistani megacity, I finally establish that urban residential enclaves are agential geo-political processes which perpetuate violence and conflict in an already divided megacity. In conclusion, I argue that this project makes important contributions for scholars and policymakers engaging with enclaves, urban governance, security and violence.