Although the interaction between alcohol and the liver has been the subject of intensive investigation since many years, several uncertainties remain to be solved. Good examples of what we need to learn are: The real number of patients with alcohol-induced liver disease (AILD), the dose of alcohol "safe" for the liver, the genetic predisposition to the damage or, on the other side of the coin, protecting from the damage. Rather recently, however, part of these questions started to be clarified, thus permitting a better definition of the role of each of these factors in AILD. In parallel to the clinical approach to AILD, the unveiling of the molecular and biochemical mechanisms involved in AILD has progressed and proved to be important in both a better understanding of the disease and, more important, in a more rational treatment of these disorders. This review will focus on what we currently know of AILD in clinical, biochemical and molecular terms and what we need to address in the future.