ABSTRACT: We undertook multi-purpose surveys of doctors who qualified in the United Kingdom between 1993 and 2012. Doctors were asked specific questions about their careers and were asked to comment about any aspect of their training or work. We report doctors' comments about working whilst acutely ill.Self-completed questionnaire surveys.United Kingdom.Nine cohorts of doctors, comprising all United Kingdom medical qualifiers of 1993, 1996, 1999, 2000, 2002, 2005, 2008, 2009 and 2012.Comments made by doctors about working when ill, in surveys one, five and 10 years after graduation.The response rate, overall, was 57.4% (38,613/67,224 doctors). Free-text comments were provided by 30.7% (11,859/38,613). Three-hundred and twenty one doctors (2.7% of those who wrote comments) wrote about working when feeling acutely ill. Working with Exhaustion/fatigue was the most frequent topic raised (195 doctors), followed by problems with Taking time off for illness (112), and general comments on Physical/mental health problems (66). Other topics raised included Support from others, Leaving or adapting/coping with the situation, Bullying, the Doctor's ability to care for patients and Death/bereavement. Arrangements for cover due to illness were regarded as insufficient by some respondents; some wrote that doctors were expected to work harder and longer to cover for colleagues absent because of illness.We recommend that employers ensure that it is not unduly difficult for doctors to take time off work when ill, and that employers review their strategies for covering ill doctors who are off work.