The aim of this study was to validate the Multidimensional Territorial Sense of Community Scale (MTSOCS), a new theory-driven sense of community scale referred to the geographical community. Starting from McMillan and Chavis' theoretical dimensions, five subscales (Membership, Shared Influence, Social Climate and Bonds, Help in Case of Need, and Needs Fulfillment) were proposed. The MTSOCS, a sociodemographic questionnaire, and several other instruments were administered to three groups of adults (for a total of 781 participants). Confirmatory factor analysis of all participants' data showed that the five subscales were good from a statistical point of view. Tests of factorial invariance showed that the five-factor model of the MTSOCS is basically the same across different-sized territorial communities: small towns, cities and metropolis neighborhoods. The total score of the scale and the five subscales showed good construct validity. A positive relationship emerged between total MTSOCS score and participation in groups/associations, cohabitation, community identification, life satisfaction, perceived social support, interpersonal trust and trust in local government. More complex relationships emerged between the five subscales and the other variables, confirming the usefulness of also having the single subscale scores. (Contains 5 footnotes and 5 tables.)