People who have mental health problems have higher morbidity and mortality rates than the general population in the UK and they are particularly vulnerable to smoking and smoking-related diseases. It is important that nurses working with these service users help them to stop smoking as part of their holistic care. Mental health nurses often have person-centred therapy skills and have the opportunity to use motivational interviewing which could help clients to consider change. However, nurses may be ambivalent about whether smoking cessation is desirable in these circumstances and prefer to prioritise mental health. Appropriate education and training should be provided so that nurses can routinely apply their skills and knowledge to support smoking cessation. In this article it is also argued that nurses should address their own attitudes to smoking, particularly if they are smokers themselves.