What organization licenses fixes rates and regulates other aspects of commercial transportation?

In the United States, the Federal Motor Carrier Safety Administration (FMCSA) is the organization responsible for regulating and licensing fixed rates and other aspects of commercial transportation, particularly for freight carriers and bus services. Additionally, the Surface Transportation Board (STB) oversees economic regulation for railroads and certain aspects of intermodal transportation. These agencies ensure safety, compliance, and fair competition within the commercial transportation sector.