The Arctic Regions have been a fascinating subject of study for a long time, mainly because of man’s strong desire to conquer the unknown. The military interest in those regions did not develop until recent years. With the straining of relations between the Soviet Union and the United States after World War II, the strategic significance of the Arctic soon became very real. This significance was appreciably diminished with the invention of intercontinental ballistic missiles but the more recent development of the nuclear missile-launching submarine has given the Arctic waters a new military importance. Of course, nuclear submarines could also be of considerable commercial interest. By borrowing the Arctic Ocean, merchant submarines could drastically shorten some of the present maritime trading routes. The exploitation of natural resources in the Arctic regions is already in process of giving new commercial meaning to the old Northwest and Northeast Passages. In the circumstances, an inquiry into the legal regime of the Arctic waters is timely. Two basic principles of the law of the sea are involved: the right of innocent passage, and the freedom of the seas. The present study will concentrate on the right of innocent passage. An investigation will be made into the legal status of the Arctic waters constituting what is commonly known as the Northwest Passage, on the North American side of the Pole, and the Northeast Passage or Northern Sea Route on the Soviet side. The basic question is whether or not the right of free and innocent passage in favour of foreign ships applies to those waters.