The third edition of this popular textbook builds on the excellent foundations laid down by the earlier editions. It provides a thorough introduction to the principles of rational drug design, adopting a 'from the bench to the market place' approach. As knowledge of biological systems has expanded and the number of techniques available for exploring and visualizing their components has increased, it has become possible to design drugs specifically for a given target. This unique insight has revolutionized the process of drug development for specific disease states, and in this textbook both novel and established approaches are incorporated. The introductory text explains the principles of drug design using real examples. These illustrate the discovery of 'lead' compounds and their manipulation to produce non-toxic drug candidates that will be successfully metabolized to interact with target receptors in a predicted fashion. In addition to fully updating the contents of the previous edition, the Editor has included important new sections on the pharmacological consequences of drug chirality, agonists and antagonists of neurotransmitters, and the process involved in proceeding from program sanction to clinical trials