LSD is making a comeback nationwide among Caucasian middle-class high school and college students. Compared to the mean values during the years 1985 to 1990, an approximately 25% increase occurred in lifetime-, annual-, and monthly-use rates of LSD, in 1993, according to the annual NIDA high school senior survey. In 1992, an increase in LSD-related arrests occurred, as did seizures of larger quantities of consumer-ready LSD. The number of LSD-related emergency room visits by adolescents increased, and intermittent LSD-related violent behavior, including suicide, homicide, and accidental death, were higher than in the previous 5-year period. Fewer high school students attribute great danger in trying LSD once or twice. The painfully learned lessons about LSD seem, sadly, destined to be relearned by the youth of the 1990s.