Recent research in sleep disorders has led to a better understanding of the causes and treatment of insomnia. A clearer understanding of the actions and side effects of sedative-hypnotic medications has led to a decrease in their use. Treatment of insomnia should be based on the following principles: (1) referral of individuals who are dangerous to themselves or others, (2) active treatment of psychiatric illness, (3) treatment of underlying disease, (4) use of non-drug treatment modalities and (5) restriction of the use of hypnotics to the treatment of transient insomnia.