This document attempts to provide a simple, evidence-based guide for implementing drug-use-prevention interventions in schools. It is in two parts. The first deals with the current evidence related to various aspects of programme planning and implementation, the second part outlines how the best practices can be implemented in a school. The information outlined in this document was collected from a review of published English language literature through the Medline database. Best practices guidelines published by national institutions involved in drug-use-prevention were also reviewed. This guide can be used by programme planners, implementers and evaluators of drug-use-prevention programmes in schools. Those working outside the school system should also find it useful.