The thrust towards trade liberalization promoted by the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO) is founded on the economic theory of comparative advantage. It is often asserted that the theory leads to the conclusion that free trade is superior to no trade, or even that some trade is superior to no trade, for all countries in all circumstances. Exports of products containing ozone-depleting substances (ODS) may similarly become less competitive if demand falls in the importing countries. Restrictions in non-Article 5 countries, such as excise taxes or labelling requirements, have acted to depress demand. A rather less contentious matter has also arisen in respect of developing countries, namely the question of 'technology dumping'. The issue was raised during 1995 by Mauritius. Suspicions were raised that some suppliers in non-Article 5 countries were deliberately encouraging such 'technology dumping' as a means of maintaining markets.