When Canada extended jurisdiction over fisheries in 1977 and created a 200-mile exclusive fishing zone, certain areas of the continental shelf, over which important migrating fish stocks passed, remained outside federal control. Excessive fishing by foreign fleets in these areas undermines Canadian conservation measures and has contributed to the problems in the Atlantic fishery. This report gives background information to the problem and analyses the difficulties in Canada's relationship with the International Commission for the Northwest Atlantic Fisheries and the North Atlantic Fisheries Organization, and the measures taken to set quotas and prevent overfishing outside the 200-mile limit.