Trade in fish is common to all societies and has taken place from time immemorial. A fisher returning with more fish than is needed to meet personal needs will tend to exchange surplus fish for other goods or services. The distribution of fish globally is very uneven. Some places enjoy abundance far beyond the needs of the local population, while others may have no direct access to fisheries resources. This means that trade has a role to play in order to achieve a more even distribution of fish around the globe where the entire marketing chain is taken into account.
Trade has always played an important part of the fisher's livelihood, even in 'subsistence' fisheries. International fish trade has been increasing very rapidly in recent decades. An estimated 45% of the world catch is now traded internationally. The widespread use of refrigeration, and improved transportation and communications has facilitated a vast expansion of trade.
The theory of international trade tells that through free and unhindered trade we could optimize the benefits of fisheries resources for humanity as a whole. The idea of free trade in the fisheries, however, is often vehemently contested because there are often tariff and non-tariff barriers to trade and other distorting factors, such as subsidies, present in trading relationships. Exchange of and access to information is vital to successful trade practices.
Important frameworks relative to trade in fisheries have been established. International trade rules have developed through several rounds of trade negotiations under General Agreement on Tariffs and Trade (GATT). The last of these, the 1994 Uruguay Round, agreed to establish the World Trade Organization (WTO) and a number of important agreements with relevance to fisheries were concluded. The FAO Committee on Fisheries has a Sub-Committee on Fish Trade, which provides an intergovernmental forum for consultations on technical and economic aspects of trade in fish and fish products.