Over the last decade, a plethora of international policies and guidelines on research integrity have been produced, and many countries have developed national codes of conduct. Recently, as a way of implementing these codes, institutions have begun offering mandatory training in research integrity for PhD fellows. This paper is based on a case study of a mandatory course in research integrity for PhD fellows at a faculty of medicine in Denmark (2017–18). The study comprised a small survey, participatory fieldwork, and interviews with six course participants, the course leader and a teacher. Based on this study, the paper shows that the PhD fellows perceived the integrity course as if it, to some extent, contributed to normalising the questionable research practice (QRP) and grey zone behaviour that the course was conceived to prevent. The interviews, however, also show that this latent normalisation must be seen in the context of the PhD fellows’ position within a strongly competitive culture, which sometimes rewards questionable behaviour. For this reason, creating a culture of research integrity cannot be accomplished by integrity training alone, it demands a wider structural change in the incentives for career advancement that sustain the current asymmetries of power.