Based on extensive participant observation research, this work presents a life history model to explain why very few of those who come into contact with narcotics become problematic consumers, that is make drugs one of the most central elements in their lives. The model covers four stages in the deviant career, two preceding and two subsequent to the individual’s narcotics debut. Prohibition and harm reduction as models for intervention are presented, and the implications for drug policy of the life history model are discussed.