Data from five study populations participating in the Cooperative Lipoprotein Phenotyping Study indicate strong relations between reported alcohol consumption and blood-lipids. Alcohol consumption was positively associated with high-density-lipoprotein cholesterol level in all populations (r from 0-16 to 0-30), the lipid level appearing to be a graded response even over the low levels of alcohol consumption reported. Less strong but consistently negative correlations were found with low-density-lipoprotein cholesterol. Plasma-triglycerides showed a modest positive correlation with alcohol. The five populations were those of the Albany, Evans County, Framingham, Honolulu, and San Francisco Studies.