International regime governing whaling is a result of difficult political give-and-take between proponents of conservation of sea mammals, who argue that overexploitation of stocks seriously threatens species’ survival, and whaling states, which are opting for maintaining a sustainable level of catch. In 1982 International Whaling Commission acting according to the International Convention for the Regulation of Whaling enacted a moratorium for commercial whaling (from 1986 onwards) and established the so-called sanctuary, an area surrounding the continent of Antarctica where this prohibition has been in effect. At the same time the above-mentioned Convention explicitly allows for issuing a special aquatic permit (JARPA) that allow its holder to conduct scientific whaling while also allowing to process and sell all the remaining by-products such as meat, blubber or bones. Japan, being one of the primary whaling states, has been repeatedly accused of abusing JARPA and using the permit to cover up commercial whaling. The opportunity to solve these controversies and at the same provide an in-depth analysis of the complex international legal regime that regulates whaling has presented itself when a case against Japan for infringing the ban on commercial whaling has been brought to the International Court of Justice.