The Drug Evaluation Classification (DEC) program, commonly referred to as the Drug Recognition Expert (DRE) program, began in the 1970s in Los Angeles, California. It quickly evolved into one of the most successful international programs aimed at deterring drug-impaired driving. The program operates under the guidelines and direction of the International Association of Chiefs of Police and is supported by the National Highway Traffic Safety Administration (NHTSA). As of March 2003, 36 states and several countries, including Canada, are involved in the program, and interest is growing in many other states and countries.