National Highway Traffic Safety Administration

The National Highway Traffic Safety Administration (NHTSA /ˈnɪtsə/ NITS-ə) is an agency of the U.S. federal government, part of the Department of Transportation, focused on automobile safety regulations.

NHTSA is charged with writing and enforcing Federal Motor Vehicle Safety Standards (FMVSS), regulations for motor vehicle theft resistance, and fuel economy, as part of the Corporate Average Fuel Economy (CAFE) system. FMVSS 209 was the first standard to become effective on March 1, 1967. NHTSA licenses vehicle manufacturers and importers, allows or blocks the import of vehicles and safety-regulated vehicle parts, administers the vehicle identification number (VIN) system, develops the crash test dummies used in U.S. safety testing as well as the test protocols themselves, and provides vehicle insurance cost information. The agency has asserted preemptive regulatory authority over greenhouse gas emissions, but this has been disputed by state regulatory agencies such as the California Air Resources Board.

The Federal Motor Vehicle Safety Standards are codified under Title 49 of the Code of Federal Regulations. Additional federal vehicle standards are contained elsewhere in the CFR. Another of NHTSA's activities is the collection of data about motor vehicle crashes, available in various data files maintained by the National Center for Statistics and Analysis, in particular the Fatality Analysis Reporting System (FARS), the Crash Investigation Sampling System (CISS, where technicians investigate a random sample of police crash reports), and others.

Other aspects of U.S. traffic safety, including road design, traffic enforcement, and crash investigation are outside of NHTSA's jurisdiction.