This study, funded by a NEFE grant to Columbia University, explores how differences in decision-making traits translate to real-world financial outcomes. At a time when the world’s 65-and-older population will double by 2035, policy changes have transferred many complex financial and health care decisions to individuals. Age-related declines in cognitive ability raise the specter that older adults facing major financial decisions may find them increasingly challenging. This study explores whether knowledge and expertise accumulated from past decisions can offset age-related cognitive declines. Using a unique dataset that combines measures of cognitive ability, knowledge and credit scores (a measure of creditworthiness that reflects sustained ability for sound financial decision making), researchers find that cognitive decline does not spell doom. Instead, domain-specific knowledge and expertise provide an alternative route to sound financial decisions. These results suggest new guidelines for designing effective interventions and decision aids across the lifespan.