The mission of the Department of Transportation, a cabinet-level executive department of the United States government, is to develop and coordinate policies that will provide an efficient and economical national transportation system, with due regard for need, the environment, and the national defense. It is the primary agency in the federal government with the responsibility for shaping and administering policies and programs to protect and enhance the safety, adequacy, and efficiency of the transportation system and services.
The Department of Transportation consists of ten individual Operating Administrations: the U.S. Department of Transportation of the Secretary, the Federal Aviation Administration, the Federal Highway Administration, the Federal Motor Carrier Safety Administration, the Federal Railroad Administration, the National Highway Traffic Safety Administration, the Federal Transit Administration, the Maritime Administration, the Saint Lawrence Seaway Development Corporation, and the Pipeline and Hazardous Materials Safety Administration. The Homeland Security Act of 2002 authorized the establishment of the Department of Homeland Security, which, on March 1, 2003, assumed management of the United States Coast Guard and the Transportation Security Administration, formerly DOT Operating Administrations.
Prior to the creation of the Department of Transportation, the Under Secretary of Commerce for Transportation administered the functions now associated with the DOT. Although many realize the creation of the new Department was a legislative priority for President Lyndon Johnson, few know how much influence the head of the Federal Aviation Agency had on Johnson’s decision.