In their own practices and in consultation, requests to psychiatrists to evaluate and treat sleep disorders in the elderly are common. The five million elders in this country receive 35%-40% of the sedative-hypnotics prescribed, despite the fact that they represent only 12% of the population. Since their sleep disturbances are usually secondary to medical, psychiatric, pharmacologic, or environmental causes, they should receive a thorough evaluation and differential diagnostic approach. Before prescribing a sedative-hypnotic, one should consider nonpharmacologic interventions and education about normal sleep changes due to aging. As a foundation for the judicious prescribing of sedative-hypnotics, the pharmacokinetic changes associated with aging are discussed.