One half our fatherlands is the ocean. This Icelandic proverb says it all. Iceland is to a large degree shaped by the ocean and the livelihood of Icelanders has been moulded by the ever-present ocean throughout the centuries. In the early 20th century almost 90% of the national income came directly from the sea in the form of fish and products thereof. This illustrates the richness of the surrounding waters. The currents of ocean water laden with nutrients hit an obstacle in the form of sub-oceanic ridges forcing them up towards the sunlight which, in the summer months lasts often 20 hours a day. This enables algae to bloom in enormous quantities, and thus form nutrients upon which the whole ecosystem thrives, a multitude of species of zooplankton convert these to food for ever larger organisms, weather it be fish, whales or birds. In the pages following this one, a few of the most important fish species of Iceland will be discussed. In all about 320 species have been recorded within the Icelandic economical zone, many, of course, are rare vagrants, others are deepwater species which only occasionally come into the hands of humans, the number of these has risen in later years due to ever more effective fishing gear, the fishing grounds are expanding to ever deeper water and marine research gets more extensive with each year. The two main species forming the base of the icelandic economy throughout the 20th century were Cod and Herring, but in the latter part of this period as the herring stocks diminished Capelin became very important and now in the last years of the century the annual catches can reach over a million tons. Altogether only about 30 species of fish can be said to have a role to play in Icelandic fisheries but the number will most likely rise slightly in the future as one seeks new ways profiting from the ocean and most of today's stocks are strictly managed by an effective quota system. The most resent species of fish caught commercially by Icelandic fishermen is the Tuna, but the future will determine weather this will become a steady source of work and income.