Schools use a large number of different strategies to reduce or prevent youth substance use and other problem behaviors. A recent national study of school- based prevention (Gottfredson & Gottfredson, 2001) showed that the median number of different pre- vention activities currently underway in the typical school was 14. The number of such activities ranged from 0 in some schools to 66 in others. Schools also make regular use of a broad array of activities. All schools use rules and policies to deter substance pos- session and use or other problem behaviors.