Written for the "15 Years of TRIPS Implementation" Symposium, this article examines why the TRIPS Agreement fails to provide effective global enforcement of intellectual property rights. It attributes such failure to five sets of challenges: historical, economic, tactical, disciplinary, and technological. The article then outlines the various actions taken by both developed and less developed countries to steer the TRIPS Agreement and the larger international intellectual property system toward their preferred positions. While developed countries push for the development of stronger enforcement norms, less developed countries resist those demands and complain about the use of bilateral, plurilateral, and regional trade agreements to establish TRIPS-plus standards. The article concludes with four lessons that can be drawn from the continuous battle between developed and less developed countries over international intellectual property enforcement norms. Given the significance of effective enforcement to both developed and less developed countries, it is the hope of this article that a better understanding of these four lessons will lead to a more balanced, robust, and sustainable global intellectual property enforcement regime.