During the past decade, universal labor standards have become the focus of intense debate. Advocates argue from humanitarian concerns and the interests of industrialized-country labor, seeking enforcement with WTO sanctions. Opponents regard labor regulation as a matter of national sovereignty, challenge the effectiveness of trade sanctions, and prefer the ILO emphasis on dialogue, monitoring and technical advice. This paper analyzes the labor standards debate, with specific attention to the analytical underpinnings of universal rules; evidence linking weak labor protections in developing countries to industrialized country wages; and the role of labor standards in WTO negotiations.