Motivational interviewing (MI) is a brief intervention that has been shown to reduce heavy drinking among college students. Because all college studies of MI to date have included a personalized feedback report, it remains unclear which of the components is necessary to produce behavior change. This study evaluated the separate and collective effects of MI and feedback among 122 "binge" drinking college students. Participants were randomized to: 1) MI with feedback, 2) MI without feedback, 3) Mailed feedback only, 4) MI with mailed feedback, or 5) Assessment only control. At an eight-week follow-up, all groups reduced their consumption, peak BAC, consequences, and dependence symptoms. For females, there were reductions in consequences and dependence symptoms in groups that received feedback, as compared to groups that did not receive feedback. For females, there was an effect of the feedback on consequences and dependence symptoms, but was no overall effect of MI on any outcome measure. (Contains 1 table.)