The increasing global prevalence of dementia and the lack of disease-modifying treatments give rise to the need for early detection of dementia-causing diseases to enable the development and targeted administration of preventative interventions. However, current methods that have potential for the early detection of dementia-causing diseases, such as positron emission tomography or cerebrospinal fluid sampling, are invasive and costly, which constitutes a barrier to the large-scale assessment of dementia risk. The Early Detection of Neurodegenerative diseases (EDoN) initiative was established by Alzheimer’s Research UK to address this challenge. As part of EDoN, digital data and low-burden clinical measures, such as blood tests, will be collected in thousands of people to create machine learning models that can detect specific dementia-causing diseases decades before noticeable cognitive symptoms arise. This effort will be supported by the development of a data platform and a digital toolkit (likely consisting of wearables and smartphone applications) that will collect active and passive physiological and behavioural measures (e.g. cognition, mood, heart rate, gait, sleep, and navigation). After extensive testing, EDoN aims to introduce the digital toolkit into annual health checks, which will allow for the early detection of dementia-causing diseases in a cost-effective, low-burden manner on a population-wide scale. Moreover, the information derived from the digital data will be used to inform lifestyle changes and to triage and stratify individuals into clinical trials or further targeted medical testing. As such, the outputs of the EDoN initiative will benefit the public, patients, carers, and clinicians, as well as the broader healthcare system and the pharmaceutical industry.