Merchant Marine
The Merchant Marines or Merchant Service was a group within the Federation that operated various survey vessels and freighters. 

, of the , formerly served on a Merchant Marine freighter in the Alpha Carinae region. His ship had at one time visited Alpha Carinae II to conduct a geology survey of the planet for a mining company. () 

The , commanded by Captain R.M. Merik, was a vessel operated by the Merchant Service. Merik joined the Service after dropping out of Starfleet Academy during his fifth year. The training requirements to command a spaceship in the Merchant Service was less than that of a starship captain. ()

William B. Harrison, who was trained as a flight control officer, was also a member of the Merchant Service. ()

See also 
Earth Cargo Service
Vulcan National Merchant Fleet

de:Handelsmarine
Federation agencies