The Kirtsaeng case serves as an important reminder that the copyright monopoly must be limited to its constitutional purpose: “promot[ing] the Progress of Science and useful Arts.” As the Court stated: “American law … has generally thought that competition, including freedom to resell, can work to the advantage of the consumer.” The exemptions and defenses provided by our copyright laws are just as essential as the rights to exclude for which they provide. Laws should not be created to protect monopolies and raise costs, whether they are for books or for prescription drugs.