The present study attempted to validate modified versions of laboratory measures of behavioral impairment from alcohol for use in the field. A total of 195 students at various BAC levels, participated during two outdoor university-sponsored events. In addition to taking nonbehavioral measures of impairment, each subject was asked to perform and evaluate a reaction time task, balance test, and give a verbal index of impairment. The actual BAC of each subject was determined using a breath-alcohol testing machine. The results indicated that self-reported measures of impairment were the best predictors of BAC. Of the behavioral measures, reaction time and body balance performance accounted for the highest portion of the variance in predicting BAC. Subjects reported that actual BAC feedback would most likely result in behavior change, followed by performance on the progressive body balance and reaction time tasks. It was noted, however, that as BAC increased, poor test performance was less likely to result in behavior change. The need for continued research into behavioral measures of alcohol impairment are discussed as a means of promoting third-party intervention and"socially responsible drinking". / Master of Science