The primary aim of this project is to evaluate the cost effectiveness of brief intervention for harmful alcohol use in trauma patients. This project will target trauma patients admitted to the Statewide Trauma Service of Western Australia (WA) based at Royal Perth Hospital who meet the criteria for harmful alcohol use. Over 1200 trauma patients admitted over a 4 month period will be administered a standardized screening tool for harmful alcohol use, and invited to participate in the project by providing informed written consent. Those who are deemed to reach the cut-off for harmful alcohol use (predicted n=480) on the standardized self-report measure will be randomly assigned to either a usual care (UC) group or a brief intervention (BI) group who will be provided with intervention that incorporates motivational interviewing conducted by a Clinical Psychologist. Detailed baseline assessments will be conducted using standardized self report and structured interview measures of alcohol use and, follow-up assessments of alcohol use, health car use, return to work, and health care outcomes will be conducted at 6 months. It is predicted that trauma patients who receive the BI will have significantly lower alcohol consumption and health care use compared to patients receiving UC which will result in cost savings to the WA Health Dept of over $500,000 within a 6 month measurement period.