Data related to IUU (and probable IUU) activity submitted to the Secretariat were used to provide an overview of the potential spatial and temporal distribution of recent IUU activity in the CAMLR Convention Area. Combining all information available to the Secretariat indicates that IUU is concentrated in the Indian Ocean Sector; however, the spatial and temporal pattern of IUU activity based on sightings data alone provides a restricted view these activities. This combined analysis also indicates the presence of IUU activity in Subarea 48.6 and more persistent activity in the Indian Ocean Sector on Ob, Lena, Elan and BANZARE banks as well as on the boundary of the Kerguelen and Heard Island EEZs. With the information currently provided to the Secretariat it may not be possible to distinguish between an apparent decrease in IUU catch and a decrease in surveillance effort that results in fewer sightings. A potential approach to understanding the actual ‘surveillance’ potential of licenced fishing vessels, by developing a better understanding of the probability that another vessel will be detected, is provided.