Alice Sullivan is Professor of Sociology at University College London, UK. She was director of the 1970 British Cohort Study (BSC70) for ten years from 2010 to 2020. She has published extensively on social, educational and health inequalities using longitudinal data analysis.

Selina Todd is Professor of Modern History at Oxford University and a Fellow of St Hilda's College, Oxford, UK. Her books include The People: The Rise and Fall of the Working Class 1910-2010 (2014) and Tastes of Honey: The Making of Shelagh Delaney and a Cultural Revolution (2019).

1. Introduction Alice Sullivan and Selina Todd 2. Two Sexes Emma Hilton and Colin Wright 3. Sex and the Brain: I Still Haven't Found What I Wasn't Looking For Sophie Scott 4. Is Womanhood a Social Fact? Kathleen Stock 5. The History of Sex: Sex Denial and Gender Identity Ideology Jane Clare Jones 6. Sex and Gender in Second-Wave Feminism Selina Todd 7. Why Do We Need Data on Sex? Alice Sullivan, Kath Murray and Lisa Mackenzie 8. Sex and Gender in Law Rosemary Auchmuty and Rosa Freedman 9. Sex, Gender, and Equality in the United States: Confusion, Conflict, and Consequences Callie H. Burt 10. Psychosocial factors and gender dysphoria: emerging theories Lisa Littman 11. The Technology of Puberty Suppression Michael Biggs 12. Schools, Feminism and Gender-Identity Theory Shereen Benjamin 13. The Children Who Wouldn't Grow Up: Gender in children's literature over fifty years Susan Matthews 14. Sex, Gender Identity and Sport Cathy Devine 15. Sex, Gender, Identity and Criminology Jo Phoenix Index