Concepts play a central part in the formulation of problems and proposed solutions to the use of substances. This article reports the initial results from a cross European historical study, carried out to a common methodology, of the language of addiction and policy responses in two key periods, 1860–1930 and the 1950s and 1960s. It concludes that the language of addiction was varied and nonstandard in the first period. The Anglo-American model of inebriety did not apply across Europe but there was a common focus on theories of heredity and national degeneration. After World War II, there was a more homogenous language but still distinct national differences in emphasis and national interests and policy responses to different substances. More research will be needed to deepen understanding of the conditions under which these changes took place and the social and policy appeal of disease theories.