Biodiversity encompasses the variety of animal and plant species, genetic resources and ecosystems on Earth. This expert report deals with the dramatic losses of biodiversity and the consequences. The losses constitute the second major challenge to human survival alongside climate change and appear to increase global health risks. Based on biological, economic, philosophical and theological perspectives, this report sheds light on the relationship between humans and nature and calls for a new appreciation of nature and biodiversity. The expert report also proposes concrete points of action to improve the situation, including a reorientation of agriculture and a more sustainable approach to land use and nutrition. The conclusion reflects on the Church, on her own actions and on her role as a civil society source of impetus for changes and dialogue.