Article 65 of the 1982 United Nations Convention on the Law of the Sea obligates states to cooperate with respect to conservation of marine mammals and, in particular, states are to work through the appropriate international organizations. The international Whaling Commission (IWC) is the principal international marine mammal organization. Following the permitted faking of two whales in the Canadian Arctic, the United States opined that, even though Canada was not a member of the IWC, Canada was obligated to adhere;to the IWC whale moratorium because of Article 65. This article examines the relationship of Article 65 and the IWC and, more generally, the scope of the duty to cooperate in Article 65.