Research suggests that Alzheimer disease (AD) pathophysiology begins prior to the clinical expression of the disease and that biomarker measures may provide direct evidence of this process. As a result, it may be possible to uncouple the diagnosis of AD from the clinical expression of the disease. The shifting boundaries between normal brain aging and disease present 3 challenges: 1) establishing guidelines for researchers and clinicians to safely and effectively communicate the diagnosis of preclinical AD, 2) setting up a process that effectively translates this diagnosis into practice and policy, and 3) adapting laws, regulations, and professional practices to the diagnosis of preclinical AD. The field of genetic testing for AD suggests how to balance a patient's desire to know his or her risk of developing dementia with a clinician's desire to mitigate the potential harms of that information. The development of diagnostic and treatment guidelines for other diseases of aging, such as cardiovascular disease, suggests the need for a National Alzheimer's Education Program to develop policies and procedures to translate preclinical AD into both clinical practice and policy. Revisions are needed to laws, regulations, and professional practices governing driving, financial management and planning, and privacy and confidentiality.