AT&T operates one of the largest wireless communications networks in the United States. With explosive growth in the highly competitive personal telecommunications market, as well as new technology demands, AT&T's ongoing challenge has been to identify and construct new telecommunications facilities on a very ambitious schedule, all the while minimizing environmental risk and ensuring compliance with the Federal Communications Commission's environmental obligation under the National Environmental Policy Act (NEPA). AT&T's business model typically involves building out a particular geographic market within about a one year timeframe, including conducting all required compliance, engineering, and development-related services.