The No Child Left Behind Act of 2001 (NCLB, 2002) has produced an explosion of interest in the use of assessment to measure and improve student learning. Initially focused on annual state tests, educators quickly learned that results came too little and too late to identify students who were falling behind. At the same time, evidence from the other end of the assessment spectrum was clear: teachers' ongoing use of assessment to guide and inform instruction--classroom formative assessment--can lead to statistically significant gains in student learning (Black & Wiliam, 1998). In this policy brief, the authors describe the role of benchmark assessment in a balanced system of assessment, establish purposes and criteria for selecting or developing benchmark assessments, and consider organizational capacities needed to support sound use. (Contains 1 figure and 1 footnote.) [For the full report, "Benchmark Assessment for Improved Learning", see ED524104.]