The goal in this course is to build upon the student¿s knowledge in chemistry and biochemistry, to provide insight into concepts relating to the chemical basis of drug action in order to make drug therapy decisions. The relationship between the biological target and the drug entity that produces a biological response requires an integrated knowledge of the drug target, the manner in which the drug interacts with the target and factors that provide the drug with a measure of specificity. The course will emphasize the significance of chemical and physicochemical properties as these factors influence the stability, solubility, bioavailability, metabolism, elimination, potency, drug half-life, drug interactions and target interactions (covalent and noncovalent binding) of the drug. The chemical and physicochemical properties of functional groups in drug and ¿target¿ structures will be emphasized. The course in not intended to cover all drugs and drug classes but will instead cover representative classes that provide broad examples of the fundamental principles associated with the chemical basis of drug action. ¿Top 200 drugs¿ (http://www.drugs.com/top200/) will be used as examples where appropriate. The course is intended to complement material presented in other pharmaceutical sciences, pharmacology, and disease and therapeutics courses.