Abstract : To recognize an alcoholic subject is a frequent request, in a medical or forensic setting. The reasons to determine the alcoholic status of an individual are many and various. Amongst the most frequent are : to decide on the origin of liver or neurological disease, put and maintain a liver transplantation candidate on a waiting list, identify the alcoholic worker to prevent work-related accidents, or evaluate the possible risk an alcoholic individual represents, for road safety or for parental custody. The specific alcohol consumption biological markers combined with clinical and psychological examinations are the best tools to identify the individuals with a problematic consumption. The use of markers belongs to the recommended actions to support patients undergoing treatment for alcoholism. It is mandatory in various situations to distinguish between the teetotaler, the moderate or problematic drinkers. Different biomarkers are described here to allow practitioners to adapt their prescriptions.