This paper investigates the potential effects that an aging "baby boomer" generation will have on gasoline use through their vehicle choice decisions. The study uses stated preference data for both conventional and alternative fuel vehicles, and measures the impact of age of survey respondent on the perceived value of vehicle characteristics such as fuel economy, performance, and body style (e.g., car vs, truck). The results suggest the possibility that average fleet fuel economy may improve in the next few years, if survey preferences translate to actual purchase behavior. No clear implications can be drawn regarding the demand for alternative fuel vehicles.