People with intellectual disabilities are living longer but are also at increased risk of health problems compared to the general population. Recognising the early signs and symptoms of cancer in a population with cognitive impairment and communication difficulties poses difficulties for family and professionals alike. Engagement in health promotion and cancer prevention is also a challenge. This postal survey explored how carers address these challenges. Forty staff, across fifteen residential facilities in Northern Ireland, completed a questionnaire about the risk and protective factors of stomach, breast, cervical and testicular cancer. They then completed questions about 90 adults with ID, recording body mass index, lifestyle choices (i.e. smoking, diet), Helicobacter pylori testing, family history of cancer and staff's health promotion and cancer prevention activities with them. The women had significantly higher BMIs than the men and only two people had been tested for the H. pylori infection. The majority of the staff had not received training in cancer prevention and most were unaware of the family histories of the people in their care. There was considerable variation in how staff approached health promotion and screening for specific cancers. The authors conclude that health promotion and cancer prevention activities for people with ID could be improved. The importance of staff training in order to raise knowledge and awareness is highlighted.