This study examined the differential prediction of alcohol use and problems by biopsychological (i.e., affective and cognitive variables) and social-environmental (i.e., social norms) variables. Undergraduate students (N = 231) were assessed twice separated by a 30-day interval. Time 1 impulsivity, affect lability, social norms, and perceived conflict between personal strivings and alcohol use were each significant predictors of alcohol use-related problems at Time 2 (T2). Structural equation models indicated that impulsivity and affect lability were related directly with use-related problems, while social norms and use-strivings conflict were related indirectly with use-related problems (mediated by use frequency). Impulsivity moderated the T2 use to use-related problems relationship. Use frequency was associated more strongly with use-related problems among more impulsive participants.