Context: Previous quantitative studies about doctor well-being have focused primarily on negative well-being, such as burnout. We conducted this study to understand residents' perspectives on well-being. Methods: We conducted 45-minute interviews with residents from 9 residencies at 2 academic hospitals in Baltimore, Maryland. From February to June 2005, we approached 49 residents through random sampling stratified by programme and gender. The semi-structured instrument elicited descriptions of well-being in residency and factors related to its promotion or reduction. Using an editing analysis style, investigators independently coded transcripts, agreeing on the coding template and its application. Results: The 26 participating residents came from internal medicine (3 programmes), psychiatry, surgery, emergency medicine, anaesthesia, obstetrics and gynaecology, and paediatrics. Six themes emerged: balance among multiple domains; professional development and temporary imbalance; professional satisfaction and accomplishment; maintaining a sense of self; stressors and coping strategies, and the role of residency programmes. Residents described well-being as a balance among multiple domains, including professional development, relationships, and physical and mental health. They viewed residency as a time for temporary imbalance, during which they invested in professional development at the expense of other domains. Some residents described feeling a 'loss of self'. Residents revealed strategies for coping with stressors and endorsed ways in which training programmes helped to enhance their well-being. Conclusions: Resident well-being was closely connected to professional development and required varying degrees of self-sacrifice with a re-balancing of personal priorities. These findings should be considered by training programmes that are interested in enhancing resident well-being.