Section 2 of the Thirteenth Amendment grants Congress power to enforce this article by appropriate legislation. In Jones v. Alfred H. Mayer Co., the Supreme Court held that Section 2 permits Congress to define the badges and incidents of slavery and pass all laws necessary and proper for their abolition. Congress has passed a number of civil rights laws under this understanding of its Section 2 power. Several commentators have urged Congress to define the badges and incidents of slavery expansively and to use Section 2 to address everything from racial profiling to discrimination on the basis of gender and sexual orientation. Jones, however, is in serious tension with City of Boerne v. Flores, which held that the Fourteenth Amendment’s virtually identical enforcement language permits only prophylactic legislation that is congruent and proportional to violations of judicially determined rights. Even more critically, Jones’s grant to Congress of substantive interpretive power runs afoul of the principles of separation of powers, judicial supremacy, and federalism that drove the Court in City of Boerne. Thus, the time is ripe to reconsider Jones and the proper scope of Congress’s Thirteenth Amendment enforcement power. This Article does precisely that, delving into the text, history, and structural implications of Section 2. Ultimately, this Article considers three ways to approach Section 2: as a limited power to prevent and remedy coerced labor; as a broad power to define the badges and incidents of slavery and to protect a wide array of civil rights; and as a prophylactic power to prevent the de facto reemergence of slavery by addressing the historical incidents and badges of the slave system. This Article concludes that the prophylactic reading of Section 2 best comports with both the original meaning of the provision and the structural principles of separation of powers, judicial supremacy, and federalism.