More and more businesses are providing their full range of services 24 h a day, 7 days a week, thus forcing their employees to work either rotating shifts or fixed night shifts. Dictates of our endogenous circadian clock prevent our brains and bodies to be indefinitely adaptable to those work schedules. Shift work operations are thus associated with serious healthy and social problems for the workers. Various interventions can counteract circadian desynchronization, sleep disturbances, and social disruption associated with shift work: changes in work schedules, sleeping and napping strategies, use of appropriately timed exposure to bright light, experimental drug treatments, or exercise.