The expansion of the Internet in speeding the flow of goods into the United States makes it important for U.S. trademark owners to consider possible steps to stem the tide of gray market goods from unauthorized dealers. U.S. trademark owners should take advantage of the growing body of case law establishing that physical and material differences between the genuine goods and the unauthorized goods constitute actionable trademark infringement. Review a number of such gray goods cases in “Preventing the Unauthorized Importation of Altered Gray Market Goods: Practical Suggestions for U.S. Trademark Owners,” originally published in Intellectual Property & Technology Law Journal, Vol. 16, No. 6, June 2004.