The Generalised System of Preferences, or GSP, is a formal system of exemptions outlined by the World Trade Organization (WTO). Specifically, it’s an adaptation of the Most Favored Nation (MFN) principle that obligates WTO member countries to treat the imports of all other WTO member countries no worse than they treat the imports of their “most favored” trading partner. In essence, MFN requires WTO member countries to treat imports coming from all other WTO member countries equally, that is, by imposing equal tariffs on them, etc.

GSPs, on the other hand, exempt WTO member countries from MFN for the purpose of lowering tariffs for least developing countries (without also doing so for rich countries). The reason for introducing GSPs was that developing countries claimed that MFN principle was creating a disincentive for richer countries to reduce and eliminate tariffs and other trade restrictions with enough speed to benefit developing countries. Adapted from Wikipedia.

The GSP agreement between South Africa and the 15 countries of the EU, as well as Norway and Switzerland, is administered by Customs & Excise.

More information about the GSPs