Attentional bias to alcohol-related stimuli is believed to be an important contributor to the development and maintenance of drug abuse. There is a considerable body of research examining attentional bias, much of which has typically utilized image-display tasks as a means to assess the phenomenon. Little, however, is known about the nature of this bias in an individual's natural environment. The current study sought to implement a novel approach to assessing attentional bias in vivo. Participants wore portable eye-tracking glasses that recorded video from their point of view and measured fixation time to objects they observed. They entered a room that was designed to represent a recreational setting in which both alcohol- and nonalcoholic-neutral beverages were placed along with other stimuli. In two different testing sessions, participants were free to visually explore the room. Participants showed similar fixation times to alcohol and neutral beverages during Session 1. Attentional bias to alcoholic beverages was observed in Session 2 because fixation time decreased to neutral but not to alcoholic beverages. The magnitude of attentional bias was positively associated with drinking habits, with heavier drinkers demonstrating a higher degree of bias to alcohol. These findings provide an ecological model of how attentional bias can develop as the net result of attention being sustained to alcoholic stimuli while diminishing to other stimuli over time. (PsycINFO Database Record