This article presents lessons learned from a story of a snowy and dangerous intersection where there was no way for pedestrians to cross. The basic theme of this paper is that if political economy is preoccupied largely with the measurement of externalities, then a goal for the testing and assessment policy community should be to devise strategies to curb and cope with the "externalities of measurement." The author briefly discusses selected problems of educational measurement in those terms and formulates a set of corresponding challenges to the measurement community that hopefully can guide the development of the next generation of tests. (Contains 2 footnotes.)