This study used daily reports of interactions in marriage to examine predictions from the conceptualization of intimacy as the outcome of an interpersonal process. Both partners of 96 married couples completed daily diaries assessing self-disclosure, partner disclosure, perceived partner responsiveness, and intimacy on each of 42 consecutive days. Multivariate multilevel modeling revealed that self-disclosure and partner disclosure both significantly and uniquely contributed to the contemporaneous prediction of intimacy. Perceived partner responsiveness partially mediated the effects of self-disclosure and partner disclosure on intimacy. Global marital satisfaction, relationship intimacy, and demand-withdraw communication were related to daily levels of intimacy. Implications for the importance of perceived partner responsiveness in the intimacy process for married partners are discussed.