The authors investigated whether impulsivity and depression affect the success of interventions to reduce alcohol use. Unadjusted and adjusted regression models were constructed to analyze the effect of impulsivity and depression on 12-month outcomes of participants of a trauma center based randomized trial of brief personalized motivational interventions versus information and advice. Of 497 problem drinkers enrolled in the program, 248 completed the 12-month follow-up. Impulsivity, male gender, being older than 35, and intentional mechanism of injury had a direct association with drinking. After interventions, a decrease in drinking was found that was unaffected by the presence of impulsivity or depression indicators.