In this innovative and challenging book, William Pardridge, a world leader in the study of the blood-brain barrier and its clinical implications, argues that brain drug development has been restricted by the failure of adequate brain drug targeting. This is an increasingly urgent problem as developments in genomics lead to new generations of therapeutic macromolecules. The author reviews the field of neurotherapeutics from the point of view of drug targeting. He surveys the scientific and clinical basis of drug delivery across biological membranes, including topics such as genetically engineered trojan horses for drug targeting, antisense neurotherapeutics, and gene therapy of brain disorders. At a time when there are few significant new drug treatments in prospect for common neurological diseases, this authoritative review will encourage a wide range of clinicians and neuroscientists to reexamine the development and use of drugs in treating disorders of the central nervous system.