The field of Neotropical primate biogeography has blossomed in the last decade, with the coupling of new statistical modeling methods and coordinate-based population-level sampling for genomic data sets. This talk considers both the drivers leading to the current diversity, distribution and abundance of monkeys in the Neotropics, and predicted future effects of human activity and climate change on primate biogeography. Monkeys first arrive in the Neotropics about 36 Ma, and all living Neotropical primates trace their ancestry to a single common ancestral population from the onset of the Neogene. The availability of lush Amazonian habitat, the rise of the Andes, the transition from lacustrine to riverine system in the Amazon Basin, and the intermittent connection between the Amazon and the Atlantic tropical forests each have been instrumental in how primates spread and diversified. The first Neotropical primates were pre-adapted to diurnal arboreal group living, making it possible on a continental scale to invade a range of forest niches not filled by native South American mammalian taxa. New competitors and predators emerged during a Pliocene-Pleistocene influx of North American fauna, peaking with the closing of the Isthmus of Panama. Humans, the extreme newcomers in the Neotropics, have influenced primate habitat and ecology over the last 13,000 years, with breathtaking transformations in the last 500 years as European colonisation led to rubber extraction, ranching, road-building, hydroelectric dam construction, forest fragmentation, vast land use modification for agriculture, and desertification. Human-mediated climate change is predicted to affect primates differently in different biomes.