Abstract The IUCN Red List of Threatened Species is currently the most comprehensive source of data on the global conservation status of animal, fungi, and plant taxa. The Primate Specialist Group (PSG), part of IUCN’s SSC, is responsible for the assessment of all primates. According to the most recent assessment, 63% of the world’s primates are currently threatened (Critically Endangered, Endangered, or Vulnerable), and the remaining are classified as Near Threatened (5%) or Least Concern (31%). Having recently celebrated 50 years, the IUCN Red List is today one of the most influential and authoritative documents on species conservation and is broadly used by conservation practitioners, policymakers, governments, funding agencies, and NGOs worldwide as a tool for setting their conservation targets and designing their strategies.