H. T. Reis and P. Shaver's (1988) interpersonal process model of intimacy suggests that both self-disclosure and partner responsiveness contribute to the experience of intimacy in interactions. Two studies tested this model using an event-contingent diary methodology in which participants provided information immediately after their social interactions over 1 (Study 1) or 2 (Study 2) weeks. For each interaction, participants reported on their self-disclosures, partner disclosures, perceived partner responsiveness, and degree of intimacy experienced in the interaction. Overall, the findings strongly supported the conceptualization of intimacy as a combination of self-disclosure and partner disclosure at the level of individual interactions with partner responsiveness as a partial mediator in this process. Additionally, in Study 2, self-disclosure of emotion emerged as a more important predictor of intimacy than did self-disclosure of facts and information.