If you peruse job listings for truck driving positions in the U.S., the necessary qualifications listed are often a high school diploma or a GED and a commercial driver's license (CDL). A CDL is a special license for operating a commercial vehicle required by the Federal Motor Carrier Safety Administration (FMCSA), the federal agency regulating the trucking industry. After passing skills and knowledge testing, most truck drivers get their CDL through their home state. Additionally, there are other requirements a driver must meet to obtain and maintain their CDL or to obtain endorsements to haul hazardous materials or particularly heavy loads.