Between 1970 and 1978 the number of convictions for alcohol-related traffic offenses nearly tripled, with much of the increase occurring between 1976 and 1977. Increases in convictions were the result of increased public relations efforts and experimental programs which created awareness and interest in the problem of alcohol use and driving. Federal funds became available for special enforcement programs such as the purchase of breath testing devices, for training police in the use of the devices. Furthermore, a series of law changes lowered permissible blood alcohol concentrations. The decreases in convictions occurred in counties having the experimental programs and having a major urban center. The urban center factor contributed to the decline because police had less time to enforce traffic laws due to other law enforcement demands. In addition, fiscal restraints reduced the size of the force, court facilities were more crowded, and the prosecutorial staff was overburdened. It was found that the increase in convictions was accompanied by an increase in arrests, but not in alcohol consumption. Convictions will probably continue to increase, but at a slower rate. Tabular data are included.