The aim of this study was to examine hypotheses from Cordova and Scott’s (2001) behavioral conceptualization of intimacy. This theory defines intimacy as a process that involves exhibiting interpersonally vulnerable behavior (i.e., behavior that is at risk of censure or punishment by another person) that is reinforced rather than punished by the other person’s response. Over time, as more vulnerable behaviors are reinforced than are punished by a relationship partner, one develops feelings of intimate safety (i.e., a sense of comfort and safety in being vulnerable with one’s partner). The current study investigated whether individuals’ perceptions of how frequently their partner engages in reinforcing and punishing behaviors during conflict are associated with change in intimate safety. Ninety one newlywed couples completed assessments of intimate safety at Time 1 and Time 2 (1 year later), and completed assessments of their perceptions of partners’ positive conflict behaviors (e.g., understanding one another’s viewpoint) and negative conflict behaviors (e.g., criticizing, blaming) at Time 2 (reporting on the previous 6 months). Results indicated that individuals who reported that their partners engaged in high levels of negative conflict behaviors experienced decreased intimate safety from Time 1 to Time 2. Further, wives who reported that their husbands engaged in high levels of positive conflict behaviors experienced increased intimate safety from Time 1 to Time 2. This study is the first to test a key hypothesis of the behavioral conceptualization of intimacy, and findings are generally consistent with the theory. This line of research has important implications for couple interventions, which often target intimacy.