The Consortium for the early identification of Alzheimer's disease–Quebec (CIMA-Q) created a research infrastructure to recruit, characterize, and track disease progression in individuals at risk of dementia. CIMA-Q established standardized clinical, neuropsychological, neuroimaging, blood (plasma, serum, RNA, genomic DNA), cryopreserved peripheral blood mononuclear cells, and cerebrospinal fluid collection protocols. These data and biological materials are available to the research community. In phase 1, 115 persons with subjective cognitive decline, 88 with mild cognitive impairment, 31 with early probable Alzheimer's disease, and 56 older adults with no worries nor impairments received detailed clinical and cognitive evaluations as well as blood and peripheral blood mononuclear cells collections. Among them, 142 underwent magnetic resonance imaging, 29 a 18fluorodeoxyglucose positron emission tomography, and 60 a lumbar puncture. CIMA-Q provides procedures and resources to identify early biomarkers and novel therapeutic targets, and holds promise for detecting cognitive decline in Alzheimer's disease. •Well-ascertained cohort of 290 community-dwelling elderly individuals in Quebec.•Large number of individuals with subjective cognitive decline studied longitudinally.•Clinical, neuropsychology, neuroimaging, and biomaterials available for Alzheimer's disease studies.