Objective: A growing body of literature has examined the ways that bystander intervention can be helpful for situations involving sexual violence. The current study examined the little researched questions of how the relationship between the bystander and the victim and the bystander and the perpetrator impacts bystander perceptions (whether the situation is a problem and how safe it would be to intervene). Method: In the present study, 545 undergraduate students were randomly assigned by gender to vignettes (low and high severity) in which they had a relationship with the victim (stranger or friend) and a relationship with the perpetrator (stranger or friend). Participants were asked to fill out questionnaires about bystander perceptions (i.e., whether they perceived the situation as a problem, whether they felt the situation was safe to intervene). Results: The relationship with the victim and/or the perpetrator differentially impacted bystander perceptions, such that having a relationship with the victim was associated with more positive bystander perceptions whereas having a relationship with the perpetrator was mixed. Moreover, consistent with prior research, participants identified the situation as more of a problem and less safe to intervene in the high severity than the low severity condition. Conclusions: Bystander intervention programs aimed at preventing sexual violence need to include content that helps participants think through how they would handle situations where victims and/or perpetrator are known to them. (PsycINFO Database Record (c) 2016 APA, all rights reserved)