The capacity of the UK GP workforce has not kept pace with increasing primary care workloads. Although many doctors successfully complete GP specialty training programmes, some do not progress to work in NHS general practice. This article explores the training experiences and perceptions of newly qualified GPs to understand how their education, training, and early experiences of work influence their career plans. A qualitative study of doctors in their final year of GP training (ST3) and within 5 years of completion of GP training (F5). Participants across England were recruited through training programmes, First5 groups, and publicity using social media and networks. Open narrative interviews were conducted with individuals and focus groups. Audiorecorded interviews were transcribed, and a thematic analysis was supported by NVivo and situational analysis mapping techniques. Fifteen participants engaged in individual interviews and 10 focus groups were carried out with a total of 63 participants. Most doctors reported that training programmes had prepared them to deal confidently with most aspects of routine clinical GP work. However, they felt underprepared for the additional roles of running a practice and in their understanding of wider NHS organisational structures. Doctors wished to avoid unacceptably heavy workloads and voiced concerns about the longer-term sustainability of general practice. Strategies to attract and retain enough GPs to support delivery of comprehensive primary care should consider how doctors' early career experiences influence their career intentions. A coherent plan is needed to improve their preparation and increase confidence that they can achieve a professionally satisfying, effective, and sustainable career in NHS general practice. © British Journal of General Practice 2019.