We must make the protection of biodiversity a public health issue, because a ‘healthy’ natural environment is essential for human beings to survive and thrive. However, it is clear that contemporary societies, through their modes of existence and production, are mistreating nature and distancing themselves from it... This issue of La Santé en action sheds light on the multiple and complex links between nature and the health (both physical and mental) of individuals, using the latest scientific research on the subject. A substantial chapter is devoted to urban renaturing policies, which require cooperation between health and environment departments within local authorities, as well as medium-term planning tools. The different articles also present a wealth of examples to illustrate the many ways in which we can reconnect with nature and its benefits, in nurseries, schools, retirement homes, shared gardens and so on.