Primates in zoos have complex social and cognitive needs that require sophisticated housing design. Leading facilities are transforming primate welfare; many still fall far short.
Primate welfare in zoos sits at the intersection of social complexity and cognitive demand — two dimensions that most zoo housing inadequately addresses. Insufficient group size limits normal fission-fusion dynamics and the social information that primates rely on for wellbeing. Barren or predictable environments fail to engage high cognitive capacity, leading to boredom that manifests as stereotypic behaviour. The best zoos have made remarkable welfare improvements through large, naturalistic mixed-species habitats, enriched feeding regimes, training programmes, and careful group management. These facilities provide existence proofs that primate welfare can be substantially improved. The gap between best practice and median practice remains, however, very large.