Background Several European countries face a shortage of general practitioners (GPs), in part due to GP attrition. Most studies of GP attrition have focussed on why GPs decide to leave. Yet understanding why GPs decide to remain may also elicit potential interventions to reduce attrition. Objectives This study examined GP graduates’ career trajectories and underlying decisions to elucidate the factors influencing GP attrition. Methods We conducted semi-structured interviews of early to mid-career general practice graduates having completed training in Belgian French-speaking universities between 1999 and 2013. We sampled participants from three categories: full-time GPs, part-time GPs, no longer working as GPs. We analysed each participant’s career trajectory and broke it down into major phases. We performed thematic analysis of the factors influencing participants’ trajectories. We compared and contrasted trajectories to develop a typology of career trajectories. Results We identified six types of career trajectories: ‘stable’ (never considered leaving general practice), ‘reaffirmed’ (had considered leaving but made substantial changes whilst remaining), ‘reactional reorientations’ (had left to escape the challenges of general practice), ‘inspired reorientations’ (had left to pursue a different job), ‘reorientations out of loyalty’ (had never wanted to practice as GPs and had remained true to their original professional aspirations) and ‘mobiles’ (valued change and did not want to set-up practice). Conclusion Reasons GPs leave the profession are multiple. The typology that emerged indicates that only some of the career trajectories would benefit from interventions to reduce attrition such as improving working conditions and providing psychological support for GPs.