French translation of The Lancet Family Planning Series reviewing the evidence for the effects of population and family planning on peoples’ well-being and the environment. The Series was released ahead of the London Summit on Family Planning. The Summit brought together participants from across the world to mobilise global action supporting the rights of 120 million additional women and girls to access family planning without coercion or discrimination. The new Lancet Series brings together the latest thinking underpinning these crucial deliberations, showing how lack of access to family planning carries a huge price, not only in terms of women’s and children’s health and survival but also in economic terms.