ANN McGILLICUDDY-DE LISI is the Marshall R. Metzgar Professor of Psychology at Lafayette College.RICHARD DE LISI is a Professor of Educational Psychology at Rutgers University.

• IntroductionForeword by Irving E. SeigelCauses, Correlates, and Caveats: Understanding the Development of Sex Differences in Cognition by Diane F. Halpern and Simay IkierExplanatory ConstructsSexual Selection and Sex Differences in Social Cognition by David C. GearyHormones, Brain, and Behavior: Putative Biological Contributions to Cognitive Sex Differences by Roslyn Holly Fitch and Heather A. BimonteSex Differences in Motivation, Self-Concept, Career Aspiration, and Career Choice: Implications for Cognitive Development by Allan Wigfield, Ann Battle, Lisa Keller, and Jacquelynne S. EcclesDomains of Human CognitionGender Differences in Language Development by Jean Berko Gleason and Richard ElySex Differences in Mathematical Abilities and Achievement by Richard De Lisi and Ann V. McGillicuddy-De LisiMaximization of Spatial Competence: More Important than Finding the Cause of Sex Differences by Nora S. Newcombe, Lisa Mathason, and Melissa TerleckiChildren's Gender Cognitions, the Social Environment, and Sex Differences in Cognitive Domains by Carol Lynn Martin and Lisa M. DinellaSummary and ConclusionsEmergent Themes in the Development of Sex Differences in Cognition by Ann V. McGillicuddy-De Lisi and Richard De LisiIndex