This is a unique work which is the culmination of the author's many years of experience in the use of the Wechsler tests in clinical assessments and as a teacher of their use. In his research, he has questioned the validity of the hypotheses used to explain the meaning of Wechsler data and the heuristic value of Wechsler data in clinical assessment. This book traces the history and development of the tests and reflects on their psychometric qualities and clinical utility. A challenging work, it asks clinicians to examine some of their most cherished hypotheses regarding the use of these tests in clinical assessment.