The issue of sleep was the subject of a report submitted to the Minister of Health in December 2006. Often overlooked in favor of other public health issues, this physiological function nonetheless raises a number of problems. It plays a fundamental role in health and well-being, contributing, for example, to the activation of the immune system, the maintenance of a constant internal temperature and energy balance, as well as to memory, the management of anxiety, and emotional balance. Sleep disorders thus affect the functioning of the body and the mind, thereby impacting many aspects of social and professional life, whether related to pathological conditions or social issues. Among the most common consequences of poor sleep is drowsiness, which leads to traffic accidents and workplace accidents linked to reduced alertness. Other, sometimes less direct consequences are worth noting, such as a reduced ability to cope with daily challenges, given that sleep contributes to learning and an individual’s psychological well-being. In this report submitted to the minister, the lack of epidemiological data on this issue in France is also highlighted, particularly regarding self-report surveys representative of the general population. This gap is illustrated by fairly clear differences in prevalence across the various studies cited in the report. While the 2005 Health Barometer survey is far from providing an exhaustive exploration of sleep-related issues, it nevertheless offers a quantitative framework across three dimensions: perceived sleep quality; the more factual occurrence of sleep disturbances during the week preceding the survey; and finally, the use of a hypnotic, measured over the past twelve months. It should be noted that the survey was not designed to explore sleep-related issues; these dimensions actually derive from different quality-of-life scales: the Duke scale for the first and the WHOQOL for the second. The analysis presented here is therefore both exploratory and fragmentary. It should be noted that the mental health section of the survey, the CIDI Short Form, also includes a question on difficulty sleeping, but this question is asked only of individuals who have experienced a period of at least two weeks during which they felt sad, depressed, or hopeless. Unlike the other two, it cannot therefore provide information on sleep at the level of the general population.[chapter excerpt]