Article 35 defines the methodology for calculating the taxable value of imported goods. The value is primarily based on the customs value determined under applicable Customs Legislation. This valuation must include all associated costs such as insurance, freight, any customs fees, and any Excise Tax paid on the goods during import. The Article explicitly states that the tax itself shall not be included in this value of supply. If determining the value through this method is not possible, the Article mandates the use of alternate valuation rules as provided for in the same Customs Legislation.