From its first edition 30 years ago, Robert Julie's A Primer of Drug Action has evolved side by side with the field it covers, capturing the current state of the science of psychopharmacology with each new edition. Furthering that tradition, the new edition takes its place as the definitive guide to the pharmacology of drugs that affect the mind and behavior as understood today. With over 40% new research citations, there is no clearer, more current presentation available on the mechanisms of drug action, etiologies of major psychological disorders, rationales for drug treatment, and the uses of psychopharmacology in patient care.