In Chile, an increasing number of Civil Society Organizations (CSO) have positioned themselves as vehicles of social and political transformation through the implementation of projects in the built environment. These organizations are driven by social goals and represent an alternative to governmental and market gaps. This paper aims to describe the role of CSO in the context of housing and urban regeneration in deprived territories. To do so, an analytical framework based on their intermediary role and the dimensions of social innovation is proposed. Based on the analysis of two group of organizations: foundations and associations, and community-led functional and territorial organizations, the paper elaborates on their role in vulnerable territories, and the results are synthetized in four main types of social innovative practices. Main results showed the contribution of SCO from their simultaneous role as implementer and catalyst, with a predominant contribution in the dimensions of processes and empowerment.