Negative affect has been implicated in risk for the development of problematic drinking behavior. Furthermore, there is evidence for reciprocal relationships between negative affect and problem drinking, such that engagement in problem drinking also predicts increases in negative affect. However, affective models of risk often fail to consider affective lability-the experience of rapidly changing mood. Although affective lability appears to increase risk for problem drinking, it is unknown if this relationship persists above and beyond other affect-related constructs (e.g. depression, anxiety) and if it is reciprocal in nature. Accordingly, we used a longitudinal survey design to examine (a) if affective lability predicts problem drinking above and beyond depression and anxiety and (b) if affective lability and problem drinking demonstrate a reciprocal relationship.