OBJECTIVES: To explore how nurses perceive their self-efficacy and performance in supporting self-management among patients with incurable cancer, and whether these perceptions differ between community and hospital nurses. SAMPLE & SETTING: 222 hospital nurses (n = 94) and community nurses (n = 128) working with adult patients with incurable cancer. METHODS & VARIABLES: An online survey included the Self-Efficacy and Performance Into Self- Management Support instrument. Possible differences in age, gender, work setting, and additional training in oncology between groups were explored. RESULTS: Nurses felt confident about their self-efficacy, particularly in assessing patients' knowledge and beliefs and in advising about their disease and health status. Nurses felt less confident in their performance, particularly in the use of technology (arranging follow-up care), but also in agreeing on collaborative goals and assisting patients in achieving these goals. Compared to hospital nurses, community nurses reported significantly higher scores on self-efficacy and performance. IMPLICATIONS FOR NURSING: More effort is needed to increase nurses' confidence in providing self-management support, with a focus on arranging follow-up care with the use of technology and on collaborating with patients in setting and achieving goals.