Despite the growing interest in social businesses, knowledge about and theorization of how these businesses change social and institutional conditions in emerging economies is scarce. This research investigates how an innovative social business model acts on institutional voids and creates social value for deprived communities. Building on insights from the literature and a longitudinal case study of a local, grassroots social business venture operating in Brazilian slums and shantytowns (favelas), we uncover and theorize eight mechanisms by which an innovative social business model brings about institutional change and creates social value. These mechanisms are: orchestrating local business networks, developing local business networks, upgrading and building cognitive capacity, legitimizing, assigning multiple roles, empowering, building a positive territorial identity (territorial de-stigmatization), and boundary spanning. Our findings have important implications for social entrepreneurs and organizations supporting social business ventures in transforming economies.