Objective. To study the impact of the number of choices and age on measures of performance in choosing a Medicare prescription drug plan. Data Source/Study Setting. One hundred ninty-two healthy individuals age 18 and older, half age 65 or older, in Claremont, California. Study Design. Participants were randomly assigned to 3, 10, or 20 hypothetical drug plans and asked four factual questions. Statistical models controlled for experimental group, age, gender, race, education, income, marital status, and health status. Primary Findings. Older age and greater number of plans were significantly associated with fewer correct answers. Although older adults were less likely to identify the plan that minimized total annual cost, they were more likely to state that they were ''very confident'' they chose the correct plan. Conclusions. The results raise concerns about the difficulties that older adults may have in navigating the wide range of drug plan choices available.Key Words. Choice, prescription drugs, Medicare, elderly A hallmark of personal freedom is choice: having alternatives available, and being given the autonomy to choose among them. Is it possible, then, to have too much choice? This would appear to be heretical, at least in economics, as consumers can always ignore the poorer alternatives. Some researchers, however, are starting to question the merits of consumers having a large array of choices. Large choice sets coupled with the desire to maximize (that is, choose the very best) have been found to be significantly related to greater sense of regret, reduced happiness, and even less satisfaction with the choices made (Schwartz et al. 2002).Given this, it is noteworthy that the Medicare prescription drug benefit has so many plan choices. In 2008, nearly all states had more than 50 standalone drug plans from which to choose. When the stand-alone plans are combined with Medicare managed care plans, older adults often faced over While a number of studies have examined the relationship between choice size and consumers' decision quality and satisfaction, little research has been devoted to examining the effects of age on decision making. This is surprising as older adults are frequently asked to make many complex financial and medical decisions (Hanoch, Wood, and Rice 2007) even though cognitive ability tends to decline with age.This Research Brief reports on an experiment in which older and younger adults were randomly assigned to a different number of hypothetical prescription drug plans that resemble those in the marketplace. Subjects, half of whom were age 65 or older, were assigned to a choice set of 3, 10, or 20 plans. We report on how age and number of plans affect objective measures of performance as well as subjective assessments of the experience, and we draw conclusions about problems associated with the design of the Medicare drug benefit.