The Transportation Security Aministration (TSA) is a U.S. government agency that was created as part of the Aviation and Transportation Security Act passed by the U.S. Congress and signed into law by President George W. Bush on November 19, 2001. The TSA was originally organized in the U.S. Department of Transportation but was moved to the U.S. Department of Homeland Security on March 1, 2003. The agency is responsible for security in all modes of transportation.