It is argued that alcoholism, and substance addiction generally, is a disease. It is not of its nature chronic or progressive, although it is in serious cases. It is better viewed as a psychological disease than a neurological one. It is argued that each time an alcoholic takes a drink, this is the result of choice; however, in cases of serious affliction, such choices are compulsive and may be called ‘involuntary’ in that they are made against the subject’s will, motivated by an overwhelmingly powerful desire that he wishes he did not have and not to act on. Alternative accounts in terms social learning theory and behavioral economics are critiqued. The conception of alcoholism as a tripartite disease composed of a ‘physical allergy,’ a mental obsession, and a ‘spiritual malady’ is defended from a contemporary scientific point of view.