Thomas R. Guskey, PhD, is Professor Emeritus in the College of Education at the University of Kentucky. He is the author/editor of twenty-five books and over three hundred articles published in prominent research journals as well as Educational Leadership, Kappan, and School Administrator. His most recent book, Implementing Mastery Learning, 3ed is essential reading for teachers, school leaders, professional learning communities, and anyone who believes that all students can learn well, achieve success, and become confident learners.