This book is a practical guide to the intellectual assessment of children and adolescents in the schools. Although primarily intended for graduate students in school psychology training programs and practicing school psychologists, it should also be useful for those involved with making decisions in schools that are based, in part, on the results of intelligence tests, including counselors, teachers, administrators, and other school personnel. In writing it, we placed particular emphasis on evidence-based practices pertaining to the use and interpretation of intelligence tests. The assessment of intelligence has long been mandated by law for eligibility determination for special education and related services. At the current time, however, there is widespread disagreement about the use and interpretation of intelligence tests. Nevertheless, none of the currently available books on intellectual assessment critically reviews the scientific evidence regarding the critical role played by intelligence tests in the schools for the determination of eligibility for special education and related services. One of the main intentions of this book was to fill that gap and to recommend best practices with scientific support.