The present study investigates reaction time (RT) as a measure of attentional deficits produced during alcohol cue exposure. Twenty-four male alcoholic patients responded to a series of computer-generated tones as rapidly as possible during baseline and again during either an alcohol cue exposure period or exposure to a control beverage (water). Patients required increased time to respond to the tones when exposed to alcohol cues. No such increase in RT was found during exposure to a control beverage. In addition, RT was significantly correlated with self-reported urge to drink. These data provide initial validation for the use of RT as an objective measure of cue reactivity. Both theoretical and clinical implications for the use of RT as a measure of the effects of cue exposure are discussed.