Eminent scientists Malcolm Potts and Roger Short view the broad panorama of human sexual and reproductive behaviour to reveal an inextricable mixture of nature and nurture - a combination of innate actions which have evolved over the millennia to adapt us to a nomadic, hunter-gatherer lifestyle, overlain by more recent cultural constraints imposed by civilization. For each of life's milestones - sexual intercourse, conception, pregnancy, birth, puberty, love, marriage, parenting, menopause and death - they describe the biology behind our actions and consider how pressures imposed by various historical and contemporary cultures have further influenced our behaviour. By looking back at the past they attempt to make sense of the present, to see how and why these cultural modifications arose, how they have contributed to the richness of human sexual behaviour, and what our biological and cultural inheritance can teach us about safeguarding the continuation of our species.