This study aimed to analyze from a case study applied to the non-governmental organization Union of Sorocaba and Region (UniOng). The relevant factors for building strategic alliances between specific OTS, which in this work was denominated as Social Alliances. Therefore, the survey noted four variables relevant to the formation of UniOng, determined by motivating factors, selection process, governance structure and evolutionary dynamics. Presenting as main results, the direct influence of social ties in the different stages of formation of UniOng, this way, the role of the social relationships is potentially motivating the decision of its economic agents.Thus, reducing some transaction costs over the alliance and allowing it to evolve to strategic relationships, being the strategy observed not only in isolation and in purely economic objectives, but in a process,that also comprises the interactions between organizations and their environment