Introduction: Globally, dementia is the most frequent form of degenerative condition in the older adult population and poses a major health burden with high socioeconomic costs. So far, attempts to find pharmacologic interventions that can change the onset or progression of dementia have been largelyunsuccessful, prompting a shift to focus on interventions aimed at modifying risk factors that occur throughout the life course. Methods: The Cognitive Function and Ageing Studies, funded by the Medical Research Council, UK, convened three multidisciplinary groups of experts, expert witnesses, and advocates to discuss the state of evidence on primary, secondary, and tertiary dementia prevention and recommend future direction for intervention studies. Results: Using the United Kingdom Parliamentary Select Committees’ approach to gathering evidence, the primary prevention working group focused their deliberation on risk factors strongly associated with dementia. The group highlighted the need for high-quality studies to assess the effects of behavioral intervention on the delay of cognitive decline and dementia onset. Discussion: The working group recommended that the development of a future dementia prevention trial should use a multimodal, multifactor, multilevel, community and individually tailored approach. 2015 The Authors. Published by Elsevier Inc. on behalf of the Alzheimer’s Association. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).