To what extent does gender influence our behavior, thoughts, and feelings? How do nature and nurture interact to shape our identities as female or male? And what are the effects of gender on the ways we are perceived and treated by others? The second edition of this important text and reference confronts the central questions pertaining to gender differences and similarities across the lifespan. Rather than focusing on a particular viewpoint, the volume is carefully designed to foster comparison among different lines of psychological research and provide a broad survey of cutting-edge work in the field.