The article describes the results of a survey of Finnish nurses (n = 882). The purpose of the study was to describe how nurses' education, working experience and their own smoking habits relate to their self-reported competence in advising and supporting clients to cease smoking. Nurses evaluated their skills fairly highly, but did not believe that advice alone was helpful to clients who wished to cease smoking. Nurses had minimal knowledge of smoking substitutes. Lower general education, a fairly short time from graduation and a history of smoking were positively related to nurses' competence to guide clients. Nurses who smoked daily were found to have better skills in giving advice and support than their non-smoking colleagues. The results have implications for the design of smoking cessation programmes. More education and guidance is required for nurses, so that they can develop their understanding and a positive view as to the effectiveness of smoking cessation programmes.