Since 2019 the ‘Floristisch-soziologische Arbeitsgemeinschaft’ (FlorSoz) has annually nominated the ‘plant community of the year’, to draw attention to Germany’s endangered plant communities in need of protection. This campaign specifically aims at supporting the conservation of plant communities and their habitats as well as at promoting political and administrative decisions and implementation processes that serve to protect and restore these ecosystems. Calthion palustris meadows will be the plant community of the year 2024. Formerly common in cultural landscapes throughout western and Central Europe, wet meadows with marsh-marigold (Caltha palustris) have become rare in most regions. Large-scale drainage and other measures of agricultural intensification, including the conversion of wetlands to intensive grassland and arable land, are responsible for the strong decline of this valuable meadow type in recent decades. Increased fertilization on the one hand and abandonment of marginal sites on the other led to changes in species composition and species loss. As an essential part of our cultural landscape, wet meadows are endangered and in some regions even threatened with extinction. Here, we outline the phytosociology of Calthion plant communities, their ecological characteristics, biodiversity and species composition. We provide an overview of the ecology, distribution and conservation status of the communities. Calthion wet meadows support a variety of mostly widely distributed, but locally rare and endangered plant species. They offer habitat to numerous vulnerable animal species, especially invertebrates and birds. With the decline of wet meadows, numerous groundnesting bird species typical of this habitat, especially waders, have also declined. As marsh-marigold wet meadows are of high ecological and functional importance and deserve prioritised protection, the causes of their decline are explained in detail. Furthermore, we discuss the ecological context of preservation, suitable conservation measures and options for restoration. Reclamation of abandoned wetlands can be considered a promising path for restoration. However, nutrient removal and rewetting of agriculturally improved grasslands, are often more difficult to implement. Diaspores have to be actively introduced and costly measures to raise groundwater levels such as sealing ditches or removing drainage systems are necessary. The short-term reduction of excessive nutrient levels is often impossible. Approaches promoting non-intensive use of wet meadows are discussed and suggestions are made to actively optimising the financial and advisory framework. For this purpose, better programs for nature conservation contracts, higher funding and other supporting instruments are essential. With the proclamation of Calthion wet meadows as plant community of the year and the publication of this paper, we intend to support conservationists and people committed to improving the general political conditions for the implementation of measures on local, regional, national and international levels. Those farmers who have managed wet meadows sustainably for decades despite adverse trends towards increased production growth deserve recognition and encouragement to maintain the traditional management. Successful measures to protect and restore species-rich wetlands are urgently needed.