Temperament is the first monograph in 40 years to present theories and basic findings in the field of temperament from a broad international and interdisciplinary perspective. The text, based on the author's four decades of personal study and data collection, thoroughly explores the physiological, biochemical, and genetic bases of temperament - incorporating age-specific methods of assessment developed through child- and adult-oriented approaches. The 147 illustrations comprise tables of the most popular temperament inventories for both children and adults, and unique data tables illustrating the psychometric features of temperament inventories based on self-rating and rating by others.