The thesis is comprised of three sections, each with their own aims. The thematic synthesis aimed to explore how the therapeutic environment of a democratic therapeutic community (DTC) is experienced, depending on whether the member/former member had attended a DTC in the community, or a DTC in a prison. The research paper aimed to explore how belongingness is experienced at the time of DTC membership; and, what happens to one’s sense of belongingness following discharge. The critical appraisal aimed to reflect on the thesis and, where possible, to synthesise the findings from the two papers. The thematic synthesis involved a total of 10 articles: five concerning DTCs in the community, and five concerning DTCs in prisons. The research paper involved semi-structured interviews with seven former DTC members – interview transcripts were analysed using thematic analysis. Three analytic themes were developed from the thematic synthesis: (i) operational elements of a DTC; (ii), connecting with the group; and (iii) facilitating therapeutic engagement. Findings from the thematic synthesis indicated that the experience of the DTC environment was broadly similar for both settings. Four analytic themes were developed from the research paper: (i) belonging and trust; (ii) spectrum of connection; (iii) being yourself; and (iv) ensuring belonging after membership. Findings from the research paper indicated that belongingness is a persistent feature of the DTC journey, beginning with an initial stage based on recognition of shared suffering, before progressing to a second stage predicated on joint participation in the therapeutic process. From the thesis, two complementary models have been proposed: (i) a model depicting the course of DTC-related belongingness; and (ii) an integrative model combining the findings from the two papers. The consistency of the findings across the thesis, as a whole, offers a degree of common understanding to the diverse DTC landscape.