Introduction Neurotransmission Principles of Drug Action Classification Variability in Response to Drugs New Drugs Development, Testing and Promotion Pharmacological Dangers and Benefits of Psychoactive Drugs Effects of Drugs on the Embryo, Fetus and Developing Young The Question of Legalization Users and Abusers of Drugs Prevention of Drug Abuse A Short and Depressing Chapter Treatment of Drug Abuse Psychopharmacotherapy Methodological Issues Psychopharmacotherapy Memory Creativity Sexual Behavior Aggression and Violence Sleep