This article describes the implementation of an innovative curriculum called Drugs-At-Work (DAW), which was evaluated in three phases. In phase-one, data collected after the third year of the study suggested that the curriculum had a significant impact on the fifth-grade participants, who in turn influenced their sixth-grade classmates the following year. In comparison to their sixth-grade baseline counterparts, the DAW participants and their classmates were significantly less likely to have used tobacco, alcohol or other illicit drugs (ATOD) and less likely to know other elementary students who did so. In phase-two, data were examined on a year-by-year basis using a modified A-B-A design. These data revealed a drop from baseline in ATOD use during the intervention years and a return-to-baseline after the program ended. In phase-three, comparisons were made among participants in the Combined Baseline Group, the Combined DAW Group and the Transition Group (those exposed to DAW but not surveyed until a year after the grant closed). These analyses revealed that the DAW significantly reduced ATOD use for the total sample and for the Mexican-American, the Anglo, and the African-American students examined separately. (Contains 1 figure and 4 tables.)