Jack Stenner and Mark Stone have been collaborating for more than forty years on issues of measurement and reading theory. Dr. Stone is a licensed clinical psychologist, board certified in school psychology and clinical psychology (ABPP). A MESA graduate, he retired as vice president and academic dean of the Adler Institute, where he taught research design and statistics. He now teaches at Aurora University and supervises doctoral dissertations. Dr. Stenner is chief science officer and cofounder of MetaMetrics Inc. He is research professor in the Applied Developmental Sciences and Special Education program, School of Education, at the University of North Carolina at Chapel Hill and chief science officer at MetaMetrics—developers of the Lexile Framework for Reading and the Quantile Framework for Mathematics. Dr. Donald Burdick, PhD, coauthored with Jack and Mark How to Model and Test for Mechanisms That Make Measurement Systems Work.