Objective: Perceived impairment and psychomotor performance following acute alcohol administration in older (ages 50-74, n = 42; 22 male) and younger (ages 25-35, n = 26; 12 male) adults were investigated in this study. Method: Double-blind, placebo-controlled alcohol administration techniques were designed to produce peak levels of breath alcohol concentration consistent with an episode of social drinking (40 mg/100 ml). Behavioral measures (Trail Making Test, Forms A and B), as well as measures of self-reported perceived intoxication and impairment, were administered on the ascending and descending limbs at common time points after beverage ingestion. Results: Results indicated that psychomotor performance differences did not parallel self-reported levels of perceived impairment. Relative to younger adults, older adults exhibited performance defi cits on the ascending limb while simultaneously reporting less perceived impairment. Conversely, on the descending limb, older adults who received alcohol reported more perceived impairment than did those who received placebo, although psychomotor performance between these two groups of older drinkers did not differ. For younger participants, a moderate dose of alcohol facilitated performance on the ascending limb; however, these differences were not reflected on the descending limb. Conclusions: These results reinforce the common knowledge that self-reported measures may not provide an accurate reflection of performance outcomes and, importantly, that older adults may be impaired even under a moderate dose of alcohol, although they may not be aware (i.e., report) of this impairment.