The U.S. Department of Education (ED) provided feedback to several states recently regarding the states' ESSA plan. Among other issues, ED raised questions regarding the use of indices for the achievement indicator. ED expressed concerns that some of the states' index systems allowed the performance of high achieving students to "mask" the performance of lower achieving students. There is no question that ESSA allows for index systems where additional points can be awarded to schools for students that score above the proficient level. Given this allowance, the author argues that index systems offer a powerful way to incentivize continued improvement for students and schools without disenfranchising lower performance individuals. This does not negate the ESSA requirement to report the percentage of students scoring at the proficient level and above for all students and by student group.