Since 2014 governance initiatives in fisheries have been forced to respond to the outbreak of ‘slavery scandals’ concerning working conditions on fishing vessels, particularly in Thailand and Taiwan. These scandals are framed through a simplified narrative that invokes slavery, human trafficking and fisheries crime, dramatic narratives being successful in making the often extremely dangerous and difficult working conditions found in off-shore fishing visible and forcing some changes in government regulations. However, these slavery narratives do not fit well with the grounded and often ambiguous legalities and illegalities found in industrial fishing and provide poor guidance towards improving these working conditions. In this paper we take up these issues drawing on fisheries research based in Thailand and Taiwan, both of which rely almost entirely on migrant workers from Southeast Asia as their workforce. We outline working conditions in these fisheries, and their relation to the management of fisheries, labour relations, and migration.