Public schools are under increased pressure to implement evidence-based substance abuse prevention programs. A number of model programs have been identified, but little research has examined the effectiveness of these programs when "brought to scale" or implemented district-wide. The current paper summarizes the application of the Adelman and Taylor's (1997) model for district-wide program implementation to the dissemination of an evidence-based parent-child drug education program called Keep A Clear Mind (KACM; Werch & Young, 1990). In addition to documenting the partnership process used to scale-up the program to a district-level, evaluation results are presented from 2,677 fifth graders in 43 schools who participated in the KACM program. Pre-post comparisons from two consecutive cohorts of students indicated a significant reduction in students' attitudes supporting alcohol use and a significant increase in parent/child communication about prevention, students' perceived ability to resist peer pressure, and their belief that it is "wrong" to use alcohol, tobacco, and marijuana. Focus groups conducted with a subset of the KACM teachers indicated great support for the KACM program, the partnership approach, and the dissemination model. Findings provide support for Adelman and Taylor's (1997) model as a framework for collaborative district-wide implementation of substance-abuse prevention programs.