The advent of globalization has made it easier for trade between various countries to take place. The volume of this trade has grown to the point that regulations, on both the national and international levels, have been put in place to monitor the trade. Part of this monitoring process is the institution of customs service at the different borders or boundaries of countries to ensure the compliance of importers and exporters with these rules. As such, the main relationship between customs and international trade lies in the fact that customs acts as a check or enforcer of various trade regulations and laws.
One of the links between customs and international trade is that customs acts as a barrier against some unscrupulous merchants in foreign countries that try to dump unwanted or even toxic materials within the territorial borders of another country. Some of these agents may try to sneak the toxic substances into the country through various guises. Without the presence of customs officials, they may succeed in doing so. Some importers or exporters may try to export dangerously substandard products to other countries. Most times, customs agents seize such items and prosecute the merchants and their agents. They may also destroy the toxic substances themselves.
Customs and international trade are connected by the fact that customs makes sure both importers and exporters obey the various related national and international laws. For instance, one country that has banned the importation of chicken products from another due to an outbreak of avian flu will instruct the customs to ensure that this ban is enforced. To this end, any related product that is discovered will be seized and destroyed. Some countries may impose trade quotas limiting the number or volume of an item that can be imported or exported in a given period. Once the limit of this quota has been reached, the customs will make sure that no importer or exporter is allowed to import or export the item.
Another connection between customs and international trade is the fact that customs prevents any international trade in illegal items. An example is that the white rhino has been declared as an endangered species with only a handful left in the wild. Some countries, however, still trade the animal, especially for its horn, which is used in making various concoctions like aphrodisiacs. Customs prevents the trade in such endangered animals, plants and other prohibited items.