Humans have been trading seafood and seafood products since time immemorial. This trade has commonly crossed national boundaries, but the scale of trade has increased markedly in the past twenty years. By and large the distilled view of nations is that trade is good and there has been considerable international pressure to encourage and facilitate trade. As trade has increased, so too have the debates over the costs and benefits due to the changes to incomes, wealth distribution, cultures and social cohesion that this trade has driven. Whilst trade has undeniable impacts on natural resources such as fisheries, it is not the sole and ultimate reason for the perilous state of many fisheries in the world. The sustainability of fisheries is ultimately dependent on good management, whether trade occurs or not. The impacts of the increasing trade in seafood need to be seen within a wider context of societal change and the capacities of communities to embrace and manage such change. The question over whether increased trade poses an opportunity or threat depends on the perspective of those who stand to gain or lose — either financially or in some other way. The tools used by societies to manage the impacts of trade-induced change are many and varied. This paper explores some of the well-known tools such as tariffs, subsidies, phytosanitary measures, international agreements and the like. It places a particular focus on the impacts of such measures on developing countries. The paper also explores some of the increasing range of private sector measures which either enhance or constrain trade. These measures have arisen as the private sector has sought to either address issues of governmental failure or exploit real or perceived demands from consumers. Finally, in seeking to address the issue of whether trade is a threat or opportunity, some speculation about the future trade in seafood and the development of measures to control and harness it are discussed.