Describing a person's first sexual intercourse provides us with a view of his or her overall sexual activity. The nature of such encounters today differs markedly from what it was fifty years ago. When women now have their first sexual experience they are on average three years younger than was the case half a century ago. Differences between men and women in this respect have, however, persisted across generations. For men, the event still amounts to an act of sexual initiation, whereas women tend to regard it as a conjugal or pre-conjugal relation. In each generation, some individuals have their first sexual intercourse early. Postponing one's first sexual experience is linked to factors that delay the process of social maturation, e.g. staying at school longer. But the timing of the first sexual relation also indicates a certain attitude to sexuality, and more generally to living as a couple and to family life as a whole. The life-courses of individuals who become sexually active at younger ages tend to be more complex than those of others : they experience a larger number of separations, and their range of sexual practices is more diverse, whereas those who become sexually active at a later age tend to have a more traditional profile, have a smaller number of partners and remain with the same partner. They are opposed to any split between living as a couple, sexuality, and sentiment. These differences in attitude and behaviour are particularly strong among men. They are far less apparent among women, especially in the older generation ; women tend systematically to associate sexuality with feelings and sentiment.