This chapter discusses how nostalgia contributes to people's efforts to meet belongingness needs. It provides a brief overview of literature that illustrates the importance of interpersonal relationships for adaptive functioning. The chapter considers research testing the assertion that nostalgia is useful in helping people meet their belongingness needs. Sedikides et al. proposed that nostalgia may operate as an indirect belongingness strategy by allowing people to revisit interpersonally fulfilling experiences from the past. The author and his colleagues provided the first empirical test of this proposal. In their first study testing this social function of nostalgia, they manipulated nostalgia by having participants write about and reflect on an experience of nostalgia or an ordinary experience from the recent past. In second study, they found identical patterns with an experimental induction of nostalgia. The results from these two studies suggest that nostalgia mobilizes the social self by making people prioritize relationship goals and increasing confidence that they can successfully complete these goals.