The Gang Resistance Education and Training (G.R.E.A.T.) Program is a school-based program targeted at middle-school students. Taught by uniformed police officers, it attempts to reduce gang activity and educate young people about the consequences of gang activity. The 9-week program was developed 7 years ago by the Phoenix, AZ, Police Department and is now taught in all 50 States and in countries around the world. The program is managed by the Bureau of Alcohol, Tobacco and Firearms, the Federal Law Enforcement Training Center and five police departments. At the 2-year mark in the program, a longitudinal outcome results study showed there were no significant differences between G.R.E.A.T. students and students who were not in the program. The program review team and some program participants decided that efforts to improve that finding should include a revision of the curriculum. A professional curriculum-writing team was hired to develop a curriculum that was more skill-based, with an emphasis on active learning, and on greater involvement by classroom teachers. A program evaluation at the 4-year follow up disclosed that the G.R.E.A.T. program had a positive outcome in some areas and outcomes leading toward positive in several other areas.