The patients of intensive care unit (ICU) suffer from sleep disorders or lack of sleep due to the particular environment. Among other problems, the noise, the lack of circadian variation of the light lead to a progressive temporal and spatial disorientation. The patients then are subject to a modification of their immunity, present agitation and confusion, neurocognitive disorders with consequences on the morbidity and the short and long-term mortality. An improvement of the sleep of the patients staying in the intensive care will have potentially an impact not only during the stay in the service but also for their future quality of life.