Aims and objectives: To describe registered nurses' reflections on discussing sexuality with patients. Background: It is known that many diseases and treatments have a negative impact on sexual health. Despite these facts, registered nurses typically do not address sexual issues with patients. Design: A descriptive design and a qualitative approach were used. Methods: Interviews were conducted in 2010 with 10 registered nurses. The data were analysed using qualitative content analysis. Results: The themes 'Doing the right thing and doing good', 'Could've, would've, should've: a nurse's conflicting feelings' and 'I just don't talk about it: sexuality as a nontopic' confirmed the notion that discussing sexuality in nursing care is still challenging and difficult for nurses, but also revealed that nurses who do talk to patients about sexual issues do so based on their strong sense of wanting to help. They felt a responsibility because of their knowledge in the area, but the topic also brought out conflicting feelings such as fear and embarrassment. Lack of time, support and places to talk to patients in private as well as prejudice were contributing factors to their not addressing sexuality. Some nurses also felt that sexuality was someone else's responsibility and a taboo subject. Conclusions: Patients' sexuality is still surrounded by silence. But factors exist that can facilitate discussion of sexuality. Nurses have a key role in detecting ill-health. This study suggests that when nurses use their knowledge and go beyond their comfort zone and address sexuality, they can identify patients' sexual problems. Relevance to clinical practice: Nurses need to understand how their knowledge can help patients who are experiencing sexual problems; they also need support from the workplace and to have access to routines that reinforce the notion that sexuality is a topic worth discussing. © 2013 John Wiley & Sons Ltd.