IUU— shing, the elements of which are discussed in detail further below in this Part, hinders the sustainable management of marine— sheries world wide. Southern Ocean— sheries and in particular the Patagonian Tooth? sh, have been targeted by IUU— shers. The text examines the response to the persistent problem of IUU— shing in 1 the Southern Ocean, by CCAMLR, as the appropriate RFMO, and Australia, a State with vested interests in the Southern Ocean by virtue of the Heard and McDonald Islands’ EEZ. This examination represents original work not only in the context of 2 Southern Ocean— sheries but in the consideration of the linkages between regional and national measures to deter IUU— shing. Faced with continued— ag State inaction, both the CCAMLR Commission and Australia have identi? ed and applied a number of measures to deter IUU— shing. These measures are examined in Parts 4 and 5 respectively. Indeed, the lack of— ag State enforcement and the development and persistence of IUU— shing are inextricably linked, a fact that will be pursued in depth in Part 2 along with the other factors identi? ed as contributing to the development of IUU— shing.