We are the Transportation Security Administration, formed immediately following the tragedies of Sept. 11. Our agency is a component of the Department of Homeland Security and is responsible for security of the nation's transportation systems. With our state, local and regional partners, we oversee security for the highways, railroads, buses, mass transit systems, ports and the 450 U.S. airports. We employ approximately 50,000 people from Alaska to Puerto Rico to ensure your travels – by plane, train, automobile or ferry – are safe and secure