This chapter interrogates the economic justifications for the doctrine of post-sale confusion at both the domestic and international levels. It begins by exploring those justifications in the trademark holder’s home market. Focusing on U.S. trademark law, this initial analysis shows the doctrine’s weak economic justifications except in cases where the presence of counterfeits will undermine the rarity or other quality-unrelated attributes of status goods. This chapter then turns to the trademark holder’s foreign markets—in particular, those in developing countries where counterfeits are frequently made. This comparative analysis shows further that the economic justifications for the doctrine of post-sale confusion are even weaker in these markets. Because many foreign jurisdictions have not adopted the doctrine of post-sale confusion, the analysis focuses on a special category of counterfeits that does not cause point-of-sale confusion: nondeceptive counterfeits. Based on the economic analyses of this doctrine in both developed and developing country markets and in relation to varying types of counterfeits, this chapter concludes by offering five recommendations for courts, legislators, and policymakers to reform trademark law in the area of post-sale confusion.