This new edition of Sex and Gender builds upon an intellectual collaboration that began a quarter of a century ago. We have seen major changes in the area described as sex differences. The pace of change has been particularly rapid in the past seventeen years since our 1985 American edition of the original 1982 book and has prompted us to radically revise our earlier texts.

Piecemeal, almost opportunistic research on sex differences has given way to theoretically driven studies summarised through the use of coherent statistical models. Perhaps the most striking change is the influence of evolutionary psychology. It has gained many adherents but does not hold complete sway. In seeking to be heard, social scientists of other persuasions have sharpened their arguments. Social role theory has become a serious contender, while a variety of psychoanalytic accounts and ethnomethodological approaches have contributed to a deeper understanding of the nature of masculinity and femininity. We hope that this volume goes some way to produce clarity in a complex and changing field.

Readers of the earlier work will recognise the familiar structure of ten chapters. The first sets the scene. Each of the eight that follows focuses on a broad theme: stereotypes, origins, developmental influences, sexuality, aggression–violence–power, fear–anxiety–mental health, the domestic sphere, and, finally, work–education and occupational achievement. In chapter 10 we consider changes and suggest the direction studies of sex differences may take in the future.