Based on the Social Identity and Social Categorization Theory framework, this study investigated how identification with the physical component of a community (i.e., the place identity), the perception of a community (i.e., the ingroup) in terms of cohesion and entitativity, and the perception of one or more territorial communities as laying beyond a community's boundaries (i.e., the outgroup) affect a psychological sense of community (PSOC). A survey was conducted with 477 residents (55.1 & female; aged 16-80 years) in the Salento region, Italy. The results showed that the more individuals identified with the spatial community, the more they felt connected to their fellow residents and the more satisfied they were with their social relationships. More importantly, the findings highlighted the contribution of ingroup-outgroup relationships on shaping PSOC, which suggests that determinants of PSOC should include both the internal identification processes and the processes that lead communities to behave towards other communities. (Contains 2 figures and 2 tables.)