The SHAHRP program was designed to reduce alcohol-related harm by bolstering students’ ability to identify and deal with high-risk drinking situations and issues. The SHAHRP study involved a quasi-experimental design utilizing intervention and control groups in 14 government secondary schools in Western Australia. Participants were 2,300 intervention and control students aged 13 to 17 years. Change was measured over a 32-month period. The intervention program was classroom-based and was conducted in two phases over a 2 year period. Intervention outcomes were analyzed by measurements of baseline context of alcohol use. Evaluation of the intervention program revealed that SHAHRP had little impact on baseline supervised alcohol consumption. However, baseline non-drinkers and unsupervised drinkers were less likely to consume alcohol in risky situations in comparison to the control groups. Furthermore, unsupervised drinkers experienced an 18.4 percent reduction in alcohol-related harm after participation in the intervention group; this reduction in harm was maintained 17 months after completion of the program. The authors conclude that that drug intervention programs in school settings should be completed in phases and that program components should be targeted to specific baseline groups. Most importantly, drug intervention programs should be timed prior to the initiation of unsupervised drinking. Figures, references