The purpose of this study was to assess the efficacy of a screening and brief intervention program for college students in a naturally occurring university-based primary health and mental health care setting. One-hundred seventy five students who met our screening criteria (>8 for men or >7 for women on the Alcohol Use Disorders Identification Test) enrolled in the project, and six-week follow-up data were collected from 120 (69%) of them. Results indicated that after receiving the intervention students reported decreased alcohol use, more accurate perceptions of other students' drinking, and increased use of protective behavioral strategies. Results also indicated that the individual-level changes in alcohol use were positively correlated with changes in the students' perceptions of drinking among their peers. Implications of the findings for clinicians, administrators, and researchers in the college drinking intervention and prevention field are discussed.