"Kids are great. It's a unique experience that everyone should have.” Except that today, 1 in 20 French people refuses to give birth. What are the motivations for this “voluntary infertility”? Deep down, do we really know why we have children? Isn't this an obstacle to personal and professional development? In an overcrowded and polluted world, isn't it selfish to take up too much space by starting a family? Aren't children too expensive for individuals and society? The author surveyed dozens of women and men for whom the "duty to procreate" rings hollow. Among these "non-parents" there are exclusive lovers, artists, careerists, religious people, the traumatized of childhood, eternal adolescents, environmentalists, convinced Malthusians, as well as feminist activists who have made of their refusal to give birth to a standard, to assert themselves in a society that extols all mothers and family values.