The concept of planetary well-being, which stresses the persistence of lineages in ecosystems, is intimately linked to species extinction risk. Avoiding extinctions is a moral issue, as wiping out the outcomes of eons of evolutionary history and their future potential is clearly unconscionable. The concept of planetary well-being is also systemic: It is understood that species, as integral parts of ecosystems, are vital for the well-being of all systems on Earth. Yet, despite international agreements to protect biodiversity, global biodiversity loss and ecosystem degradation has continued unimpeded over the past decades. We review the role of goals and targets in the UN Convention on Biological Diversity, stressing the importance of accountability. We suggest that extinction risk assessments of the International Union for Conservation of Nature’s Red List, and associated country-level Red List Indices, provide valuable tools for guiding conservation action and for monitoring the state of planetary well-being.