They are: (1) heroin addiction promotes criminal activity by placing a heavy financial burden on the addict which cannot normally be met through legal means; and (2) connections in the criminal subculture which distribute heroin facilitate and encourage criminal solutions to the problem of financing heroin addiction. Life-history interviews with 32 heroin addicts suggest that both hypotheses are, at best, true for only certain periods in addict careers, while at other periods the assumed causal dynamics are neutralized or reversed. These findings suggest some specific refinements and alterations in treatment and enforcement strategies and complicate current theoretical speculations and empirical findings on the drugs-crime connection. (Author abstract)