This industry group comprises establishments primarily engaged in providing specialized services to the air transport industry.

This industry group comprises establishments primarily engaged in providing specialized services to the rail transport industry. Establishments engaged in the operation of railway terminals and stations, and the maintenance of railway rights-of-way and structures are included.

This industry group comprises establishments primarily engaged in providing specialized services to the water transportation industry.

This industry group comprises establishments primarily engaged in providing specialized services to trucking establishments, bus operators and other establishments using the road network.

This industry group comprises establishments primarily engaged in acting as intermediaries between shippers and carriers. These establishments are usually referred to as freight forwarders, marine shipping agents or customs brokers. They may offer a combination of services which may span transportation modes.

This industry group comprises establishments, not classified to any other industry, primarily engaged in providing specialized services to transportation establishments. Establishments engaged in packing, crating and otherwise preparing goods for transportation are included.