Exposure to alcohol advertising during very early adolescence predicts both beer drinking and drinking intentions 1 year later. Children at extremely high levels of overall advertising exposure were subsequently 50 percent more likely to drink and 36 percent more likely to intend to drink as those at low levels. Previous studies suggest that youth might be more likely to drink as a result of exposure to alcohol advertising. To provide evidence regarding the possibility of a causal relationship, this study tested effects longitudinally and included a variety of controls for known predictors of underage drinking. Two in-school surveys of 1,786 South Dakota youth measured exposure to television beer advertisements, alcohol ads in magazines, in-store beer displays and beer concessions, radio listening time, and ownership of beer promotional items during sixth grade and drinking intentions and behavior at seventh grade. Tables, figures, and references