The report (in two volumes) summarizes the results of a comprehensive review and analysis of the problem of alcohol and highway crashes in the United States. Both the nature of the alcohol-crash problem and societal responses to that problem are treated. Epidemiologic studies, experimental studies, and countermeasure po-economic, travel, and attitudinal characteristics of two types of users, express bus passengers and non-urograms are examined in the review. The short-term future of the alcohol-crash problem is projected and conclusions and recommendations relative to future research and action programs are developed.