ABSTRACT. The authors used an event-contingent daily recording strategy, the Rochester Interaction Record (RIR), to examine the motivational dynamics of interpersonal relations. Using hierarchical linear modeling, the authors demonstrated that social interactions were more pleasant when participants felt autonomous, competent, and related. Autonomy, competence, and relatedness consistently predicted interaction quality, regardless of (a) the length of the interaction; (b) whether it was dyadic or in a group; and (c) whether it was an interaction with family, friends, or acquaintances. However, participants were more likely to report feeling autonomous and related when they were interacting either with family members and friends or in a dyadic situation. These results suggest that experiences of autonomy, competence, and relatedness may make a good day partly because they produce satisfying interpersonal experiences.