Context This paper aims to consider why general practitioners (GPs) teach, in particular by defining the longitudinal supervisory relationships between rural clinician-preceptors and students. Methods A total of 41 individual semi-structured interviews were conducted with GPs, practice managers and students. All interviews were audiotaped, transcribed and analysed for emergent themes. Results In this study preceptors identified many ways in which precepting added value to their roles. However, themes relating to the doctor-student relationship were central to GP preceptors' experiences. These developed in chronological order and resulted in changes in the triangular relationship between doctor, patient and student in the consultation. Discussion Interpretive findings identify that the motivators for precepting represent a group of constantly changing interconnected factors that contribute to the defining of preceptors as central members of their professional community of practice. This critical finding challenges the simplistic organisational concept that universities can recruit and retain GPs by offering increased rewards. This paper introduces four clinical preceptor models, which involve the roles of, respectively: the student-observer; the teacher-healer; the doctor-orchestrator, and the doctor-advisor. Symbiosis between student learning and patient care was found to occur in the doctor-orchestrator model. Conclusions The evolution of doctor-student relationships in long-term student placements explains how students become more useful over the academic year and sheds light on how GPs are changed through precepting as part of the complex process by which they come to recognise themselves as central members of the rural generalist community.