Jessica JunkerSilviu O. PetrovanVictor Arroyo-RodríguezRamesh BoonratanaDirck BylerColin A. ChapmanDilip ChetrySusan M. CheyneFanny M. CornejoLiliana Cortés-OrtizGuy CowlishawAlec P. ChristieCatherine CrockfordStella De La TorreFabiano R. De MeloP. FanCyril C. GrueterDiana C. Guzmán-CaroEckhard W. HeymannIlka HerbingerMinh D. HoangRobert H. HorwichTatyana HumleRachel A. IkemehInaoyom S. ImongLeandro JerusalinskySteig E. JohnsonPeter M. KappelerMaria Cecília M. KierulffInza KonéRebecca KormosKhac Q. LeBaoguo LiAndrew J. MarshallErik MeijaardRussel A. MittermeierYasuyuki MuroyamaEleonora NeugebauerLisa OrthErwin PalaciosSarah K. PapworthAndrew J. PlumptreBen M. RawsonJohannes RefischJonah RatsimbazafyChristian RoosJoanna M. SetchellRebecca K. SmithTene SopChristoph SchwitzerKerry SlaterShirley C. StrumWilliam J. SutherlandMaurÍcio TalebiJanette WallisSerge WichElizabeth A. WilliamsonRoman M. WittigHjalmar S. KühlFaculty of Social SciencesFaculty of Business AdministrationBorneo Nature FoundationOperation Wallacea Ltd.Bristol Zoological Society LtdInstituto Chico Mendes de Conservacao da BiodiversidadeUniversidad San Francisco de QuitoCentre Suisse de Recherches Scientifiques AbidjanUnited Nations Environment ProgrammeUniversity of Western AustraliaUniversität GöttingenUniversity of CambridgeThe University of QueenslandUniversity of OklahomaUniversity of California, San DiegoLiverpool John Moores UniversityStony Brook UniversityUniversity of Michigan, Ann ArborUniversity of StirlingUniversity of California, BerkeleyDurham UniversitySun Yat-Sen UniversityRoyal Holloway, University of LondonUniversidade Federal de Sao PauloOxford Brookes UniversityUniversidade Federal de VicosaMahidol UniversityUniversity of KwaZulu-NatalZoological Society of LondonDeutsches PrimatenzentrumBirdLife InternationalUniversität LeipzigInstituto de Investigaciones en Ecosistemas y SustentabilidadMax Planck Institute for Evolutionary AnthropologyMcGill UniversityUniversity of CalgaryNorthwest UniversityFoundation for Sustainability of EcosystemInstituto Nacional da Mata AtlânticaBorneo FuturesInstituto Pri-MatasGerman Centre for Integrative Biodiversity ResearchAsociación Primatológica ColombianaWorld Wide Fund for NatureUaso Ngiro Baboon ProjectGroupe d'Etude et de Recherche sur les Primates de MadagascarWildlife Conservation Society-NigeriaWorld Wildlife Fund (WWF) GermanyGlobal Wildlife ConservationGibbon Conservation CentreConservación Internacional ColombiaCommunity Baboon SanctuarySouthern Institute of EcologyCentre Suisse de Recherche Scientifique2020-11-182020-11-182020-09-18BioScience. Vol.70, No.9 (2020), 794-80315253244000635682-s2.0-85090308279https://repository.li.mahidol.ac.th/handle/20.500.14594/59818© 2020 The Author(s) 2020. Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe barriers for testing primate conservation interventions and propose actions to improve the conservation evidence base to protect this endangered and globally important taxon.Mahidol UniversityAgricultural and Biological SciencesArticleSCOPUS10.1093/biosci/biaa082