Marine Resources Group operating companies provide a number of green and blue water services. The companies include Foss Maritime Company, based in Seattle, Washington, and its subsidiary companies: Boston-based Constellation Maritime Company and Seattle-based America Cargo Transport Corp. The MRG family of companies also includes Oakland-based AmNav Maritime Services, and two companies based in Honolulu, Hawaii: Hawaiian Tug and Barge and Young Brothers. MRG companies are also active outside the U.S. The Mercosur Shuttle Group consists of three companies, CMSA, CMSP and CMSU, and is operated from Buenos Aires, Argentina.