The Harmonized System (HS) came into effect in 1988. It has been developed and maintained by the World Customs Organization (WCO). WCO is an independent intergovernmental organization based in Belgium, with more than 200 member countries.
Its activities include measures to secure interpretation of the Harmonized System and periodically updating it in view of the technological developments and changes in international trade patterns.
The entire process is managed through the Harmonized System Committee that represents the HS convention and the Contracting Parties. The committee decides on classification questions, prepares amendments and settles disputes. It also updates the HS every 5-6 years.
The Harmonized Tariff Schedule (HTS) became effective in 1989. It sets out the tariff rates and statistical categories for all products imported into the US. The schedule is published and maintained by the U.S. International Trade Commission. The commission also makes recommendations regarding amendments needed to keep the HTS consistent with international nomenclature.
The U.S. Customs and Border Protection is the only agency that administers the HTS at American ports of entry and also provides legally binding advice and rulings on matters concerning the classification of imports.