Following a decade during which drug use by adolescents was viewed by many parents and other adults as a normal phase of development, the 1980s have been marked by growing awareness of the risks and costs of illegal drug use. Yet, despite the many successes of a burgeoning parents' movement, stimulated by the active leadership and support of the President and Mrs Reagan, drug use persists as a significant threat to the health and well-being of American youth. Physicians are in a powerful position to deliver health promotion messages to patients and their parents and have an obligation to do so whenever possible. Messages delivered on a routine basis can be influential in promoting smoking, alcohol, and drug abstinence. These messages should begin early and continue throughout childhood to reinforce and strengthen the development of healthy attitudes and behaviors. The pediatrician must never be reluctant to express his or her own views regarding the health consequences of drug and alcohol use to patients or their parents. Informed pediatricians represent formidable opposition to individuals who argue that "experimental" or "recreational" use of illicit substances during the developmental years is inevitable, normal, or harmless.