Clofibrate is known to be an inducer of alcohol- and acetaldehyde dehydrogenase. Therefore, male rats were offered increasing amounts of alcohol over a period of three months. Eventually they could choose between a 30% alcohol solution and tap water which was available ad lib. Animals were sacrificed after further 1 1/2 months of clofibrate feeding. Before clofibrate feeding voluntary intake of alcohol was 3.47 g/kg per day and increased up to 7.77 g/kg per day, i.e., by 123% within the clofibrate feeding period while the alcohol intake of controls increased from 3.84 to 4.88 g/kg per day, i.e., by only 27%. Food consumption increased in the clofibrate control group, whereas in the alcohol drinking clofibrate group the total caloric intake increase was due mainly to the enhancement of alcohol consumption. Relative liver weight was increased by clofibrate in the non-drinking as well as in the drinking group by 59%. Measurements of triglycerides and cholesterol exhibited changes typical for clofibrate in ethanol drinking and non-drinking animals. Probably the clofibrate-alcohol interaction results in accelerated ethanol metabolism and increased metabolic tolerance by induction of the ethanol detoxifying system in the liver.