Professor Schepers has written a text on the theory and practice of psychological test construction that will help students, teachers, and professional psychologists to master the complexities of the art and science of test construction. The book has many strengths, but two in particular stand out. Firstly, Professor Schepers expertly derives all the formulas of reliability from a single formal definition. The second strength is the way in which Professor Schepers extends concepts and techniques that were originally developed for dichotomous test items (as typically found in ability tests) to polytomous items (as typically found in attitude and personality inventories). The book contains "psychometric wisdom" and insight-the product of many years of deep study and experience in test construction and development