To develop theory about how and why the supervision and support model used by the Remote Vocational Training Scheme (RVTS) addresses the professional and non-professional needs of doctors (including many international medical graduates) who are training towards general practice or rural generalist fellowship while based in the same rural or remote practice. We conducted a realist evaluation based on the RAMESES II protocol. The initial theory was based on situated learning theory, networked ecological systems theory, cultural theory and geographical narcissism theory. The theory was developed by collecting empirical data through interviews with 27 RVTS stakeholders, including supervisors, participants and RVTS staff. The theory was refined using a project reference and a stakeholder advisory group and confirmed using individual meetings with experts. Theory about how the contexts of person, place and program interacted to address professional and non-professional needs. The RVTS program offers remote access to knowledgeable and caring supervisors, real-time tailored advice, quality resources and regular professional networking opportunities, including breaks from the community. It worked well because it triggered five mechanisms: comfort, confidence, competence, belonging and bonding. These mechanisms collectively fostered resilience, skills, professional identity and improved status; they effectively counteracted the potential effects of complex and relatively isolated work settings. This theory depicts how a remotely delivered supervision and support model addresses the place and practice challenges faced by different doctors, meeting their professional and non-professional needs. The participants felt valued as part of a special professional group delivering essential primary health care services in challenging locations. The theory could be adapted and applied to support other rural and remote doctors.