INTRODUCTION: Limited data illuminate how resident doctors view their important roles as teachers, supervisors and role models. Analysing qualitative data about resident teachers' self-perceptions can offer helpful insights. METHODS: One year after a randomised trial of a residents-as-teachers curriculum at a university medical centre, we invited its 23 resident participants to participate in semistructured interviews. We interviewed 21 third year residents from internal medicine, family medicine and paediatrics, including 12 intervention residents who had been randomly assigned to receive a 13-hour teacher training programme and 9 control residents who had received no training. We used grounded theory techniques. Two investigators independently content-analysed the transcribed interviews for emerging themes and we then developed a schema for a third investigator to code the transcripts. RESULTS: Three key themes consistently emerged: enthusiasm for teaching (current and future), learner-centredness, and self-knowledge about teaching. Compared with control residents, the intervention residents expressed greater enthusiasm for teaching, more learner-centred and empathic approaches, and a richer understanding of teaching principles and skills. Most intervention residents wanted to continue teaching during and after training. Fewer control residents enjoyed their current teaching, and fewer still wanted to teach in the future. The control residents seemed easily frustrated by time constraints and they often expressed cynicism and blame toward learners. DISCUSSION: One year after participating in a randomised trial of a residents-as-teachers curriculum, generalist residents revealed fairly consistent perceptions of their teaching roles. Teacher training may offer residents lasting benefits, including improved teaching skills and satisfaction.