The purpose of the project was to obtain information on the operational effectiveness of a questionnaire and interview procedure, previously developed by HSRI, for identifying problem drinkers. In the present study, cooperation was obtained from 12 Alcohol Safety Action Projects in which the HSRI procedures were used. In order to obtain information on the statistical effectiveness of the procedures in discriminating between problem drinking drivers and others, among DWI defendants, responses from 709 drivers, in three ASAPs were analyzed. Scores on the questionnaire and interview protocol were compared against an objective criterion consisting of BAC at time of arrest and number of previous DWI and other alcohol offenses. The procedures were found to have good validity and reliability. The analyses indicated that revisions to the previously recommended cut-off scores are needed when used with DWI defendants, to maximize the discriminability between problem-and non-problem drinkers. Users of the procedures were surveyed to obtain their judgments of the usefulness of the questionnaire and interview;​ the procedures were generally well received. Based on comments received, some questionnaire items were reworded.