This chapter discusses the urban structure of China’s post-reform cities arguing that it constitutes a form of enclave urbanism: an urban structure with high degrees of cultural, functional and economic sorting of groups and activities over distinct areas, separated by physical, legal and/or social boundaries. Reproducing forms of in- and exclusion, this structure has many similarities with the structure of cities elsewhere. However, criticizing five often-implicit assumptions of the enclave urbanism literature, this chapter employs Manuel DeLanda’s (2016) assemblage theory to understand enclaves as assemblages of heterogeneous elements that are themselves part of multiple assemblages operating on various ‘scales’. The resulting relational comparative view guides attention to both similarities and differences between enclaves in different locales. Applying this view, this chapter first presents the literature on China’s urban enclaves, before discussing consequences of China’s enclave urbanism for the access to and exclusion from urban services, and for social networks respectively. Observing inadequacies in the Anglophone urban China literature, the chapter culminates in a research agenda.