Addiction concepts became established in the wake of the great expansion of the availability of psychoactive substances through the globalization of the age of European empires and the industrial revolution. Addiction was a way of understanding (and locating either in the substance or in individual deficiencies) the contradictions between ready availability and the demands for sobriety imposed by the new means of production and transportation. Originally applied to alcohol, addiction concepts were soon applied to other substances. The elusive place of addiction concepts in current international drug control treaties is considered. On the one hand, the "serious evil" and "danger" of addiction is a preambular justification for the treaties; on the other hand, the addict and addiction otherwise disappear from consideration, except in terms of technical criteria for the inclusion of substances.