The Federal Motor Carrier Safety Administration (FMCSA) is responsible for regulating large trucks and buses. As part of its mission, the FMCSA SAP Program develops and enforces regulations to improve safety on our nation's highways. The FMCSA's Safety fitness Determination (SFD) program is one way the agency works to improve safety. The SFD program uses a data-driven approach to identify and intervene with motor carriers that pose the greatest risk to safety.