The Isles of Scilly Steamship Company (ISSCo) founded in 1920 operates the principal shipping service from Penzance, Cornwall, to the Isles of Scilly, located 28 miles (45 km) to the southwest. It provides a year-round cargo service together with a seasonal passenger service in summer. The name of the company's principal ferry, the Scillonian III, is perhaps better known than that of the company itself.
The company is based in the Isles of Scilly Travel Centre Penzance It also owns Isles of Scilly Skybus Ltd, which operates are services to the Isles of Scilly and sight seeing flights.