The Lancet Commission on the future of care and clinical research in autism.

Competing Interests: Declaration of interests CL reports royalties from Western Psychological Services for diagnostic instruments; is on scientific advisory boards or projects for Tilray, Roche, Gateway, Springtide, and Greenwich Biosciences; and is supported by grants from the US National Institute of Mental Health (R01HD081199, R01MH115363, R01MH104423–02, and R01MH114925). TCh reports consultancy fees from Roche and Servier; royalties from Sage Publications and Guilford Publications; grants from the UK Medical Research Council (grants number MR/K021389/1 and MR/R011427/1), the UK National Institute for Health Research (grants number 13/119/18 and RP-PG-1211–20016), the EU Horizon 2020 programme (grant number 814302), Innovative Medicines Initiative (grant agreement number 777394 and AIMS-2-TRIALS, which receives support from the EU Horizon 2020 programme, European Federation of Pharmaceutical Industries and Associations, Autism Speaks, Autistica, and Simons Foundation Autism Research Initiative); and grant support from MQ Mental Health Research, The Waterloo Foundation, Epilepsy Research UK, the Charles Hawkins Fund, and the Baily Thomas Foundation. EA reports consulting fees from Roche and Quadrant; funding from Roche and SynapDx; non-financial support from AMO Pharma; book royalties from APPI and Springer; editorial board honoraria from Wiley; a patent (US20160000365A1) for an anxiety meter; is supported by the Ontario Brain Institute (POND network), Canadian Institutes of Health Research, Autism Intervention Research Network on Physical Health (funded by the Health Resources and Services Administration), US National Institutes of Health, Brain Canada, and the Azrieli Foundation; and is the Canada Research Chair in translational therapeutics in autism spectrum disorder and Dr Stuart D Sims endowed chair in Autism. BB is supported by US National Institute of Mental Health grant (1R01HD82127). AHa was supported by grants from the South-Eastern Norway Regional Health Authority (grant numbers 2018059 and 2020022) and by the Research Council of Norway (grants number 274611 and 288083). RJ reports funding from Australia's National Health and Medical Research Council. JC is supported by National Institute of Mental Health grants NIMH09902, NIMH081148, NIMH083707, NIMH80011, and U10MH66764. PC is supported by Simons Foundation Powering Autism Research and the Maternal and Child Health Bureau of the Leadership Education in Neurodevelopmental Disability. TCa reports personal fees from Western Psychological Services. LS reports being a consultant for Roche, Yamo, Teva, Impel, and Janssen Pharmaceuticals; book royalties from Oxford University Press, Guilford Press, and American Psychological Association Press; and licensing royalties for the Parent-Rated Anxiety Scale for Autism Spectrum Disorder from Cogstate and Yamo. PPW reports being employed by Clinical Research Associates, a non-profit organisation that is developing an experimental drug treatment for autism. CMF receives royalties for books on autism spectrum disorder, attention-deficit hyperactivity disorder, and major depressive disorder; grants for the A-FIPP randomised controlled trial (FR2069/8–1, 8-2), awarded by the German Research Foundation, and for the EU-AIMS2-TRIALS (H2020 777394) and EU STIPED (H2020 731827), awarded by the EU. CK is supported by grants from the Health Resources and Services Administration of the US Department of Health and Human Services (UA3MC11055), the US National Institutes of Health (R01HD098248, R01HD095973, P50DC018006), the US Department of Defense, and the Goldman Foundation (3104). APi receives questionnaire royalties from WPS. AHo reports personal fees from GW Pharmaceuticals. PSz receives research funding from the Canadian Institutes of Health Research and royalties from Guilford Press and Simon & Schuster for books. PSh reports support from the Health Resources and Services Administration of the US Department of Health and Human Services under the Autism Transitions Research Project (UJ2MC31073). VS is supported by the National Institute for Health Research (grant numbers EME 13/119/18, RP-PG-1211–20016, and 15/162) and a grant from Autistica (number 7262). GD reports grants from the UK Medical Research Council and Grand Challenges Canada, outside the submitted work. All other authors declare no competing interests.