The World Trade Organisation (WTO) comprises 149 member states. It lays down rules for trade between nations.

From 1950 to 2000, world trade increased by a factor of 22. With such intensive trade, animal diseases and diseases transmissible from animals to humans (zoonoses) spread more rapidly.

Countries threatened by animal diseases sometimes take action to protect themselves which can lead to excessive restrictions on trade. The agreement on Sanitary and Phytosanitary (SPS) measures is an attempt by the WTO to counteract such restrictions. The agreement is based on international WTO standards regarding food safety and the health of fauna and flora.

Member states have to report changes in their legislation to the WTO by means of SPS notifications. If there is a risk of an animal disease being imported, special measures may be necessary after a scientific risk assessment, e.g. temporary import bans. These measures are described in a SPS notification.

All WTO members are free to examine whether the measures taken by a country are reasonable. In Switzerland, the Federal Veterinary Office (FVO) reviews all current SPS notifications that relate to trade with animals and animal products.

If a country is not in agreement with a measure, it may lodge an objection with the WTO through its representative. If no agreement is reached, a WTO arbitration procedure is initiated.