This research examines bystander willingness to report three different crimes to the police or campus authorities among a college student sample (n = 295). Twelve original vignettes varied anonymity when reporting, bystander’s relationship with the offender (friend or stranger), and crime type. A factorial analysis of variance showed that main effects were found for crime type, bystander’s gender, and bystander’s relationship with the offender; anonymity was not significant. The physical assault was the most likely to be reported (4.47), followed by theft (3.26), and sexual assault (2.36). Women were more likely than men to report each crime type, and bystanders who were good friends of the offender were less likely to report than strangers. No two- or three-way interactions were significant, but a significant four-way interaction indicated that anonymity, relationship with the offender, and bystander’s gender predicted willingness to report for the sexual assault scenario.