A survey using a community-based sample (N = 650) was conducted to identify motivational and cognitive predictors of individuals’ propensity to intervene against intimate partner violence (IPV). A hierarchical regression analysis showed that motivational factors accounted for the greatest proportion of the variance in self-reported propensity. Specifically, personal norm (i.e., an individual’s felt obligation to intervene) was the strongest individual predictor, followed by affective response (i.e., the extent to which an individual responds to IPV with negative emotions). Although cognitive factors explained only a small portion of the variance, the propensity to intervene was significantly higher for respondents who perceived IPV as a prevalent issue and who did not view the perpetrator as responsible for the solution of IPV. The findings suggest that attempts to facilitate public intervention should target specific, rather than general, aspects of public norms and beliefs about IPV.