Since the early 1990s, science has addressed anthropogenic climate change as a health issue. From about 2000 onwards, the scientific literature and evidence on the health effects of climate change has been rapidly increasing. Global warming is now considered an "existential threat to humankind," and leading health organizations call climate change "the defining issue for public health in the 21 century" or a "public health emergency."In recent years, climate change as a health issue has become more and more prominent in health communities on the national and international level.The growing importance of this issue in the international health community and the stages, milestones, and topics of this development are described and what health professionals and health organizations can do to protect health from climate change is demonstrated. The decisive role of The Lancet and the reports of its international commissions, the British Medical Journal (BMJ), and the World Health Organisation (WHO) in setting the agenda is underlined. Important actors, organizations, initiatives as well as new concepts like "planetary health" and "planetary boundaries" are introduced. In the German health sector, however, climate change - apart from niches - has not been much of an issue so far. Neither in the health sector, climate policies, nor climate movement the connections between climate change and health are sufficiently understood, considered, or implemented. A look beyond borders shows what might be possible and necessary in view of the possibly "greatest crisis we have ever faced."The article is based on the author's experience, cooperation, and exchange with parties that are engaged with the issue and on years of literature research. He initiated the campaign of German doctors calling on their pension funds to divest from fossil fuels and is a founding and present board member of the "German Alliance on Health and Climate Change," which was founded 2017.
