Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission.

Competing Interests: Declaration of interests SA declares grants from the Indian Council for Medical Research (2022–25), the Government of Karnataka (2022–23), Rotary Bangalore Midtown (2022–23), Lowes Services India (2022–25), and Wellcome Trust (2023–26); payment for expert testimony received by Indian Council of Medical Research and Ashoka University; and a travel grant paid by University College London for being part of the Lancet Commission. SB declares grants from National Institute for Health and Care Research (NIHR), Economic and Social Research Council, Engineering and Physical Science Research Council, Canadian Institute for Health Research, the Alzheimer's Association, the Alzheimer's Society, Health Education England, Alzheimer's Association, Alzheimer's Society, and Health Education England. He has held the following positions: Non-Executive Director Somerset NHS Foundation Trust, Trustee of the Alzheimer's Society, Executive Dean of the University of Plymouth, and Pro-Vice Chancellor of the University of Nottingham. AB acts as a consultant for Lilly, TauRx Pharmaceuticals, and Eisai and carries out medico–legal work for solicitors. NCF declares consulting fees from F Hoffmann-La Roche, Eli Lilly, Ionis, Biogen, and Siemens; participation in data safety monitoring or advisory board for Biogen; and being a member of the Research Strategy Council for the Alzheimer's Society. LNG declares owning tailored activity programme licences. MK declares grants from Wellcome Trust (221854/Z/20/Z), the Medical Research Council (R024227), the National Institute on Aging (R01AG062553, R01AG056477), and the Academy of Finland (350426). KYL declared fellowship from Medical Research Council. EBL receives grants from the National Institutes of Health (NIH) and royalties from UpToDate. GL declares support for the manuscript from the Alzheimer's Society, the Alzheimer's Society UK, and UK Research and Innovation, who gave grants to pay for travel and accommodation. She is supported by the University College London Hospitals' NIHR Biomedical Research Centre, by North Thames NIHR Applied Research Collaboration, and as an NIHR Senior Investigator and has grants from NIHR Health Technology Assessment, NIHR Programme Grants for Applied Research, the Alzheimer's Association, the Norwegian Research Council, and Wellcome, outside of the submitted work. She works with the Alzheimer's Society as a member of the Research Strategy Council and is a trustee of Nightingale Hammerson care homes. KR declares grants from Canadian Institutes of Health Research, the Canadian Frailty Network, and Research Nova Scotia; royalties from Biotest, Qu Biologics, AstraZeneca UK, BioAge Labs, Congenica, Icosavax, KCR, Faraday Pharmaceuticals, Synairgen Research, Enanta Pharmaceuticals, Pfizer, Boehringer Ingelheim International, Fresenius Kabi Deutschland, Baycrest Geriatric Care, and Shanghai Ark Biopharmaceutical; payment or honoraria from University of British Columbia, Fraser Health Authority, McMaster University, Chinese Medical Association, Wake Forest University Medical School Centre, University of Omaha, and Atria Institute; participation on data safety or advisory board for EpiPharma; and leadership of the Canadian Consortium on Neurodegeneration in Dementia, Cap Breton University, and Nova Scotia Health. KS declares support from the Japan Society for the Promotion of Science fund (22H03352, 21KK0168, 16KK0059). LSS declares support from Della Martin Foundation, the NIH (P30 AG066530, R01 AG051346, R01 AG062687, R01 AG051346, R01 AG055444, P01 AG052350, R01 AG053267, R01 AG074983, R01 AG063826), Abbott, Biohaven, Biogen, Eisai, and Eli Lilly and consulting fees from AC Immune, Cortexyme, Alpha-cognition, BioVie, Athira, Eli Lilly/Avid, Corium, Lundbeck, Merck, Muna Therapeutics, Novo-Nordisk, Neurim, NeuroDiagnostics, Ono, Otsuka, Roche/Genentech, Cognition, Lighthouse, GW Research, ImmunoBrain, and Bristol Myers Squibb. AS declares grants from Wellcome Trust, the Alzheimer's Association, Brain Canada, and the NIHR. YY declares support from the National Natural Science Foundation of China (72374013) and the National Key R&D Program of China (2023YFB4603200, 2023YFC3606400). SW declares an NIHR doctoral training fellowship. GS has participated on advisory boards for the following pharmaceutical companies manufacturing drugs against Alzheimer's disease: Biogen, Roche, and Eisai. LG is an inventor of a training program for health and human service professionals in an evidence-based tailored activity intervention, the Tailored Activity Program; she and her respective universities are entitled to fees. All other authors declare no competing interests.