Major biodiversity data and knowledge gaps persist across the Americas (well established). Basic exploration is incomplete, especially in the richest biodiversity areas. Brazil contributed the largest number of new plant species to the global inventory from 2004 to 2016, and 42 per cent of recently described new mammals species worldwide between 1993 and 2008 came from the Americas (well established) {3.6}. In South America experts predict that around 50 per cent of marine biodiversity remains undiscovered (established but incomplete) {3.6}. Research on functional diversity and the relationship between biodiversity and ecosystem functions across taxonomic groups is growing but remains scarce in some subregions. Enormous data gaps persist at the biome level in all subregions. Despite its very high biodiversity, South American houses the fewest georeferenced species occurrence records per unit area, while the highest number is in North America, despite much lower richness {3.6}. Major challenges for the future are: scaling up from ecological studies to the biome level, coordinated conservation efforts in biomes that cross country boundaries, making all biodiversity data available online, and the production of standardized biodiversity data useful for policymakers {3.6}.