The Harmonized System

As an internationally standardized product nomenclature, the Harmonized System (HS) is used by WTO Members in their schedules of concessions and in the definitions of product coverage for a number of WTO agreements. The Harmonized System is normally amended by the World Customs Organization every four to six years. These amendments pose considerable challenges for the WTO and its Members. On the one hand, Members need to periodically update their historical schedules of concessions into the latest nomenclature. On the other hand, these amendments may have implications for the definition and thus also the implementation of some WTO agreements where the product coverage is defined in terms of the HS. In either case, the product codes and/or descriptions in the old HS version need to be transposed precisely into those in the new version of HS nomenclature in order to retain the historical concessions or the product coverage unchanged. Given the complexity of HS amendments, this process could be very technical and sometimes tricky. This paper starts by providing an overview of the HS amendments and proposing a categorization of those HS changes in the context of transposition. It then looks back at the history of the introduction of the HS and its subsequent amendments into the WTO schedules and assesses the difficulties and problems which have been faced by WTO Members. On the basis of such analysis, it introduces the successful procedures and methodologies used by WTO Members and the WTO Secretariat to deal with the recent HS2002 transposition. The paper also discusses the implications of the HS amendments to three WTO agreements and the possible approaches to transpose their product lists into a new HS nomenclature.