Abstract
Polysomnography in drug development is used to detect desirable and undesirable effects of drugs on normal and disturbed sleep. Although this method is essential for the approval of new hypnotic drugs, it is quite often neglected in the development of drugs that show unwanted side effects on normal sleep. In this review, the requirements for qualified polysomnography are described, the strong and weak points of the method are discussed, and its importance for the drug development process is pointed out.