The WCO Harmonized System Committee conducts a periodic review of the HS to reflect technological changes and patterns of international trade and recommends changes to the SYSTEM. The first round of these amendments came into effect on January 1, 1992 (HS92). On 1 January 1996, a second, larger set of amendments (SH96) came into force and a third came into force on 1 January 2002 (HS2002). A Fourth Amendment came into force on January 1, 2007 (HS2007). The database allows users to access and study preferred commercial texts and associated rules of origin, either by selecting a country from a drop-down list, on a world map, or by selecting a list of agreements in alphabetical order. The database also has a feature that allows users to compare the basic texts of the rules of origin from two to four different agreements. In addition, the database will reproduce copies of original evidence (certificates of origin) used in the agreements. The customs policy on CCS is set out in Chapter 2 of Schedule D of the revised Kyoto Convention (RKC) and the guidelines for free zones contain technical specifications for this chapter. Chapter 2 contains 21 standards covering a wide range of customs procedures and controls related to RSCs. To date, the RKC is the only international agreement that contains provisions in this area. Chapter 2 (free zone) of Schedule D of the revised Kyoto Convention (RKC) defines a free zone as «a part of the territory of a party in which imported goods are generally considered import duties and taxes outside customs territory.» WCO members and the business community in all WCO regions are faced with an increasing number of preferential trade agreements, often with very different rules, which can be both very complex and difficult to enforce. In addition, customs administrations are required to enter into negotiations for the introduction of new preferential regimes, often in conjunction with other public services. In addition, the management and application of rules of origin is often the sole responsibility of customs authorities.
There is no international definition of origin, although there is a distinction between two systems: preferential and non-preferential. In the case of preferential origin, everything is based on bilateral or multilateral agreements. In the case of non-preferential origin, each country applies its own rules, although non-preferential rules are harmonised for all relevant EU Member States within certain regional economic unions.