Alison L. Bailey is Professor of Human Development and Psychology at the University of California, Los Angeles, working on issues germane to children’s linguistic, social, and educational development. She has published widely in these areas, most recently in Annual Review of Applied Linguistics, Teachers College Record, Educational Researcher, and Review of Research in Education. Her previous books with Margaret Heritage include Formative Assessment for Literacy, Grades K-6 (Corwin Press) and Self-Regulation in Learning: The Role of Language and Formative Assessment (Harvard Education Press). Other recent books include Children’s Multilingual Development and Education: Fostering linguistic resources in home and school contexts (Cambridge University Press), and Language, Literacy and Learning in the STEM Disciplines: How language counts for English Learners (Routledge Publishers). She serves as a member of the National Assessment of Educational Progress (NAEP) Standing Committee on Reading, the National Council on Measurement in Education (NCME) Task Force on Classroom Assessment, and the National Academy of Sciences’ Consensus Committee on English Learners in the STEM Disciplines. Margaret Heritage is an independent consultant in education. For her entire career, her work has spanned both research and practice. In addition to spending many years in her native England as a practitioner, a university teacher, and an inspector of schools, she had an extensive period at the University of California at Los Angeles (UCLA), first as principal of the laboratory school of the Graduate School of Education and Information Students and then as an Assistant Director at UCLA’s National Center for Research on Evaluation, Standards and Student Testing. She has also taught courses in the Departments of Education at UCLA and Stanford University. She is a regular presenter at conferences across the United States and internationally. Her most recent book with Corwin, co-authored with Christine Harrison, is The Power of Assessment for Learning: Twenty Years of Research and Practice in UK and US Classrooms.