The purpose of this study was to investigate the attitudes of registered nurses (RNs) about the importance of involving families in nursing care. A sample of 634 randomly selected Swedish RNs completed the instrument, Families' Importance in Nursing Care-Nurses' Attitudes (FINC-NA), and reported holding supportive attitudes about families. High scores were found for the subscales: family as a resource in nursing care, family as a conversational partner, family as a burden, and family as its own resource. Variables that predicted a less supportive attitude about involving families in nursing care included being a newly graduated nurse, having no general approach to the care of families at the place of work, and being a male nurse.