Official arrest records were examined for 1971-86. This provided a data base of 2 years prior to the initial lowering of the minimum age (from 21 years old to 18), a baseline of 7 years at the minimum purchase age of 18, a baseline of 5 years during the upward transition from 19 to 21, and 2 years of data since the reinstatement of the 21-year-old minimum purchase age. The arrest rate for juveniles per 10,000 of the child population (under age 18) was computed for three categories of alcohol-related offenses: drunk driving, disorderly intoxication, and general liquor law violations. When the minimum legal age for purchasing alcoholic beverages was lowered to 18 years old, youths in the under-18-year-old age group had higher instances of automobile fatalities, drunk driving, and disorderly intoxication. When the minimum age was raised, these rates decreased. 1 table, 3 figures and 11 references.