Sleep is essential for optimal functioning as it allows the brain to catalog experiences, prime memory, and regulate hormones. Getting less than 7-8 hours of sleep per night can negatively impact concentration, creativity, mood and productivity. Different stages of the sleep cycle, including deep sleep and REM sleep, are important for physical renewal, learning, memory processing and higher level thought. Lack of sufficient sleep, especially REM sleep, makes tasks like concentrating, multitasking and understanding subtleties more difficult. Managers can get more from their sleep by avoiding caffeine late in the day, creating a restful sleep environment, and taking short 10-20 minute power naps if needed.