The aging population in western countries and the increase in longevity make the problem of recognition and treatment of sleep disorders more acute in the elderly population. The risk of evolution of sleep disorders in the elderly leads to a greater weakness of their physical health, a greater dependence on their environment, and finally to more frequent recourse to institutionalization. We investigated sleep habits, sleep disorders and psychiatric diagnoses, physical illnesses and psychotropic drug consumption in a representative sample of the general population of France. Interviews were performed over the telephone by lay interviews using the Eval Knowledge Based System, a computerized system that guides the interviewer through the interview process, 6966 subjects were contacted, and 5622 interviews (80.8% of the potential sample) were completed. The sample was divided into four age groups: 15 to 44 years old (56.4%); 45 to 64 years old (25.6%); 65 to 74 years old (10.8%) and 75 years old or more (7.2%). Earlier bedtime, long sleep latency, spending more time in bed with a reduction of nocturnal sleep time, nocturnal awakenings and daytime naps were found more frequently in "young old" (65 to 75 years old) and "old old" subjects (75 years old or more). Daytime naps and spending more time in bed with a reduction of nocturnal sleep time also distinguished "old old" subjects from "young old" subjects. About half of "old old" subjects who complained about their sleep did not get a diagnosis of sleep disorder, nor psychiatric disorder (52.4%). An insomnia diagnosis was given in 14% of cases (mostly primary insomnia-6.7%) and a psychiatric diagnosis in 33.4% of cases (mostly anxiety diagnoses-28.2%). The rate of psychotropic drug consumption was 11.7% (95% Cl: 10.9% to 12.5%) for the entire sample. This consumption dramatically increased with age: 4.8% between 15 to 44 years old; 15.6% between 45 to 64 years old; 24.3% in "young old" subjects and 32.8% in "old old" subjects. Psychotropic drug consumption was distributed as follows: 6.4% of the sample used anxiolytic, 2.7% hypnotic, 1.5% antidepressant and 0.9% hypnotic and anxiolytic together. The chronic use (at least one year) of hypnotic or anxiolytic drugs was frequent in "old old" subjects (92.6% and 80.2%, respectively) and "young old" subjects (74% and 78% respectively). The assessment of sleep by the physician should be made part of the routine clinical examination of older subjects. Review of the etiology of insomnia complaints is crucial in the choice of treatment. The reflex of psychotropic prescription in case of poor sleep is neither sufficient nor desirable, especially because of the risk of chronic use of the prescription. These data underline the importance of educating physicians about consequences of long-term utilization of these drugs and on the need for sleep hygiene measures as alternative solutions for treating insomnia complaints.