The Compressed Air Challenge (CAC) is a voluntary collaboration of industrial users, manufacturers, distributors and their associations, consultants, state research and development agencies, energy efficiency organizations and utilities. CAC's primary activity has been to develop and provide resources to educate industry and encourage changes in practices that improve the efficiency and productivity of compressed air systems. These resources include best practices manuals, fact sheets and training programs. The programs are targeted to equipment vendors and end-users. CAC is a national program that has had a significant impact in the Midwest. Between February 1999 and September 2004, the CAC and its sponsors have hosted more than 50 training sessions in the Midwest, reaching more than 2,000 people. Trainees saved an average of 148,563 kWh per year after attending the training sessions. This is approximately $7,400 per year on energy costs for each person who attends a training session. Midwest Partners include: Association of Ingersoll-Rand Distributors, Compressed Air and Gas Institute, Compressor Distributors Association, Energy Center of Wisconsin, Iowa Energy Center and the State of Illinois.