Human, animal and environmental health form a single unit - with a very significant impact on the perspectives of sustainable development. The COVID 19 pandemic is not the first time that the close link between human, animal and environmental health is demonstrated. As a result, the concept of "One Health" has also gained importance on the political agenda. To implement it, KfW Development Bank is pursuing a series of approaches which are presented and evaluated in a new interdisciplinary specialist publication. The commitment in agriculture, for example, the preservation of biodiversity, water and natural resources and health protection already contributes to the goals of One Health. In future, it will be increasingly important to take interactions between sectors and structural interrelationships into account.