UNLABELLED:According to major theories of behavioral prediction, the most proximal psychological predictor of an individual's behavior is that individual's intention. With respect to interdependent behaviors such as condom use, however, relationship dynamics influence individuals' power to make decisions and to act. OBJECTIVE:The current study examines how relationship dynamics impact 3 condom use relevant outcomes: (a) the individual forming his or her own intention to use condoms, (b) the couple forming their joint intention to use condoms, and (c) actual condom use behavior. METHOD:We conducted a 2-wave longitudinal study of young heterosexual adult couples at high risk for HIV infection involving the collection of both individual- and couple-derived data. RESULTS:Results demonstrate the importance of both person (e.g., biological sex and dispositional dominance) and relational (e.g., relational power and amount of interest in the relationship, operationalized as commitment and perceived alternatives to the relationship) factors in predicting condom use intentions and behavior. Individuals who are lower in dispositional dominance are likely to incorporate their partner's intentions into their own individual intentions; the intentions of individuals who have less interest in the relationship are more highly predictive of the couple's joint intention; and the intentions of men and individuals higher in relationship power are more likely to exert a direct influence on condom use. CONCLUSIONS:These findings have implications for improving the health of high-risk individuals, including suggesting situations in which individuals are highly influenced by their partners' intentions.