The Harmonized Commodity Description and Coding System (Harmonized System) has been adopted by the major trading nations of the world, including Canada. Decisions of the European Court of Justice are influential for interpretation of the Harmonized System. According to these decisions, goods should be classified under the Harmonized System on the basis of their physical characteristics, while factors that relate to use after importation should be considered only if they are reflected in the physical characteristics. The author rejects this narrow approach and argues that interpretation will be successful only if it is done in light of the full commercial context, including use after importation, advertising, distribution, and market indicators such as price. The article reviews Canadian case law since implementation of the Harmonized System in 1988 as well as some decisions interpreting the pre-1988 Canadian nomenclature, which contained many tariff items that depended on the end use of goods after importation.