Another area in which interests need to be reconciled is trade policy. Measure introduced to protect health may restrict the free movement of goods or individuals. On the other hand, trade policy measures can have, indirectly, both negative and positive effects on the health of a country’s population. This potential conflict of interest is taken into account in one of the major exceptions to the WTO’s basic principle of unrestricted market access: measure essential to protecting health are permitted in principle, provided they are not discriminatory or used as a covert means of restricting international trade.