Objective: This study evaluated the effectiveness of a large-scale intervention designed to reduce alcohol abuse among adjudicated college students. Participants: Participants were college students mandated to attend a Brief Alcohol Screening and Intervention for College Students (BASICS) program and a randomly selected comparison group of high-risk drinkers. Methods: Data were collected from January 2006 through December 2008. A total of 1,390 (67%) students in the intervention group and 508 (61%) students in the comparison group completed baseline and 6-month follow-up surveys. Results: Male students in the intervention group significantly decreased their drinking at follow-up, whereas those in the comparison group increased their drinking. Women in both the intervention and comparison groups decreased their drinking at 6 months. Conclusions: When implemented with fidelity, BASICS is a generally effective intervention, especially for male adjudicated college students. The intervention was most effective for moderate- and high-risk drinkers. (Contains 8 tables and 1 figure.)