As in many other areas around the globe, enclosed residential spaces have proliferated in Southeast Asia since the 1990s. Recent publications have presented such gated communities as ‘porous enclaves’, implying multiple socio-spatial dynamics of movements through gates and walls. However, the enclave model does not suffice for analyzing the relational dynamics generated by enclosed residential estates. The concept of ‘ecotonal space’ and social geography are used to show, in the case of Cambodia’s capital Phnom Penh, that the enclosure and its borders are producers and products of multiple social, spatial, economic and political relations, both symbolic and material. Property developers assert their position as an emerging elite in the city’s society and politics, a process based on different types of everyday relations they have with the inhabitants of their residential estates and territorial institutions. The enclosed residential estate can serve as a resource for deploying new power relations. Consubstantial with the neopatrimonial nature of the Cambodian economy and politics, this process is a response to the opacity and uncertainty of real estate markets and urban development.