By 2030, the number of Americans age 65 and over has been projected to reach about 71.5 million, nearly 10 million of whom will be 85 and up. The good news is that many seniors report better health, greater wealth, and higher levels of education than seniors in past decades. Research on how to stay active and sharp and how to grow wiser is proliferating—it's up to us to act on the information now.