How does mood influence people's willingness to disclose intimate information about themselves? Based on recent affect-cognition theories and research on interpersonal behavior, 3 experiments predicted and found that people in a positive mood disclosed more intimate, more varied, and more abstract information about themselves. In contrast, people in a negative mood were more attentive to the behavior of others and reciprocated self-disclosure from their partners more accurately. This effect was obtained in hypothetical situations (Experiments 1 and 2) and in realistic computer-mediated interactions as well (Experiment 3). Experiments 2 and 3 confirmed that mood effects on self-disclosure were mediated by information processing style. The role of affect in information processing and relationship behaviors in particular is discussed, and the implications of these findings for everyday interaction strategies and for contemporary affect-cognition theorizing are considered.