You are between 55 and 65 years old. Your doctor has just told you about a new test that will reveal, with 90 percent accuracy, whether or not you will be diagnosed with Alzheimer’s disease within the next 15 years. Do you want to be tested?

This is not science fiction—it’s barely fiction at all. Advances in neuroimaging, genetics, and our understanding of Alzheimer’s disease mean that some doctors are already providing Alzheimer’s prediction. Many others will follow in the next few years. What will this mean for employment, health insurance, long-term care insurance, retirement planning, and retirement? What will it mean for families, for aging politicians, for Supreme Court hopefuls? Will we know that the tests really are accurate? Who will regulate them? And how?