Personality and Temperament includes cutting-edge developments in the trait approach to personality presented by leading authors in the world and is dedicated to the work of Alois Angleitner. The central topics of this research are presented in the three parts of this book: Part I focuses on recent and future trends in behavioral genetic studies of personality and temperament traits, like gender differences in the heritability of traits and the behavior genetic study of the structure and covariation among personality and ability traits. The biological basis of individual differences is the focus of Part II. It explores the role of the most important biological systems for bringing about individual differences in temperament and intelligence and includes studies on the evolutionary sources of psychological processes. The structure and measurement of personality and temperament are treated in Part III. The authors focus on novel approaches and answers to the conceptualization of trait structure and highly sophisticated analyses of critical issues in the measurement of traits and their consequences both for theories of personality and temperament as well as for the interplay between personality and behavioral responses in social situations.