[The comeback of "one health" and global health: let us not make the same mistakes again].

The COVID-19 pandemic has led to a rediscovery of the concept of "One Health" and the idea that animals, humans and the environment are intimately linked. This is not a new concept, but it is still labile, contributing to inevitable confusion. There is still a lack of action on the ground, and "One Health" fails to integrate all three dimensions. This editorial aims to share six challenges for implementing the "One Health" approach in order to avoid the pitfalls of other global health initiatives. One Health programmes cannot be relevant and sustainable without the active involvement of communities. This deployment implies the necessary decolonisation of health, i.e. a rethinking of how programmes are governed, financed, formulated, implemented and evaluated, with and for the citizens and countries concerned. It cannot be done without addressing social inequalities in health and power issues. This approach leads to questioning the exploitation models of both agricultural and natural resources. Thinking about "One Health" implies thinking about issues and interventions from an intersectoral, inclusive and participatory perspective, from an interdisciplinary, if not transdisciplinary perspective, and understanding the resulting complexity. Finally, research findings should be taken into account to build public actions. Considering these different challenges and adopting a systemic and interdisciplinary perspective anchored in local contexts according to a participatory and inclusive approach thus seems essential to us to respond in an appropriate, relevant and sustainable manner to the issues associated with "One Health".