Sex and Gender is a substantially revised second edition of a classic text. Adopting a balanced and straightforward approach to the often controversial study of sex differences, the authors aim to introduce the reader to the fundamental questions relating to sex and gender in an accessible way at the same time as drawing on research in this and related areas. New developments which are explored in this edition include the rise of evolutionary psychology and the influence of Social Role Theory as well as additional psychoanalytic and ethno-methodological approaches which have all contributed to a greater understanding of the complex nature of masculinity and femininity.