The peri-urbanization process brings new challenges to governments of peripheral municipalities. They require stronger capacities to deal with economic, social and environmental impacts such as rural and urban in-migration, land speculation, conversion of agricultural and forestry land into urban uses, negative environmental externalities and de-territorialization and re-territorialization of livelihoods. Here, urban governance in the form of collaborative social networks seems to be crucial for better solutions for the benefit of people. However, the ability to manage collaborative networks is closely related to the way relationships are established inside the organization as well as its institutional context. Based on a social capital approach, this article explores the structure and processes of an intra-government network that lead its actors to work together to try to improve the quality of life of the local residents and control expansion of urbanization over agricultural land.