This paper presents the findings of an investigation into a mental health promotion initiative in young offender institutions across England. The study involved a survey of staff attitudes towards mental health promotion, and surveyed practice run by these staff. Analysis of staff descriptions of mental health promotion revealed a degree of confusion and a lack of clarity over the definition of mental health and mental health promotion. The concept of a mental health promotion initiative which aimed to improve the well‐being of the general inmate and staff population was not a shared vision and not part of the core work of either health care staff or prison officers. It is recommended that any future campaigns on mental health or health promotion should have a central lead, with some flexibility to allow for the development of local initiatives, fostering local relationships and partnerships.