This document adopts as a final rule interim amendments to the Customs Regulations which conformed those regulations to existing statutory provisions and judicial precedent regarding the assessment of interest due to underpayments or overpayments to Customs of duties, taxes and fees pertaining to imported merchandise, including interest on those duties, taxes and fees. The majority of the conforming changes reflect the terms of section 505 of the Tariff Act of 1930, as amended by the Customs Modernization provisions of the North American Free Trade Agreement Implementation Act. The conforming amendments also reflect changes to 19 U.S.C. 1505 and to section 321 of the Tariff Act of 1930 (19 U.S.C. 1321) regarding interest that were made by the Miscellaneous Trade and Technical Corrections Act of 1996.