The author of this article challenges a common assumption made by both critics and defenders of standardized-testing technology (or psychometry), namely that standardized tests "measure" something (culture, ability, etc.). It argues that psychometric practice cannot be classified as a form of measurement and instead is best understood as a marker of social value, an inherently political act. The chapter concludes by suggesting the significance of this argument for debates regarding "standards," "accountability," and educational assessment more generally. (Contains 9 notes.)