State legislatures are largely responsible for the vital transportation systems that are key to America's economic growth, mobility and quality of life. Transportation issues addressed by NCSL include access and mobility, airports and aviation, alternative fuels, bicycles, commercial vehicles, driver's licenses, drunk and impaired driving, freight mobility, funding and finance, gas taxes, highway infrastructure and management, hazardous materials ("hazmat") transportation, motor vehicles, ports, public transit, rail, REAL ID, registration and titling, traffic safety, transportation technologies, waterways and much more.