Nurses are particularly likely to experience impaired sleep due to their stressful working conditions and rotating work/sleep schedules. No studies have examined the joint effects of stress and alcohol use on sleep parameters. Understanding which of these factors may be more important for sleep may help inform the design of more effective intervention efforts to improve sleep among nurses. Multiple regression analyses were used to examine stress and alcohol use as predictors of insomnia symptoms. The results suggest that both increased stress and alcohol use may be associated with impaired sleep among nurses, although stress may be a more robust predictor.