Social norms for alcohol use are important influences on individual college student drinking. The present study extends social norms research by examining alcohol-related consequences and, in particular, whether similar misperceptions exist regarding the frequency and evaluation of these consequences over time. College student drinkers (N = 624) participating in a longitudinal study completed Web-based surveys assessing alcohol use and related consequences, as well as their beliefs about frequency and evaluation of consequences for the typical college student. Findings suggest that students overestimated how often typical college students experience negative consequences and underestimated how negatively other students evaluated those consequences. Finally, results support a bidirectional model for alcohol-related consequences, possibly indicating a reciprocal, mutually influential feed-forward loop of norms and consequences that promotes maintenance of college student drinking and consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved). (from the journal abstract)