Having traced the context and the history of the development of the consumption of heroin in France and presented the results of the main general population surveys, the article concentrates on the connexion in France, from the end of the 1980s, between activity related to heroin (sale, use) and the deprivation and precariousness which characterised many quartiers of the large cities, particularly the suburbs. A residual and devastating phenomenon, the consumption of opiates can be seen as an epidemic, transferred from one person to another through the networks of the informal economy. The role of social networks and the impact of criminal justice sanctions have contributed progressively to lifestyles being fixed around these activities, which both provide a stable framework (groups consuming the drugs and those protecting and facilitating resale) and one which is vulnerable (taking risks, contamination, negative discrimination, criminalisation). Analysis of the trends and the evolution towards polyconsumption of different drugs allows us to see the links between these lifestyles (taking similar risks, diversion by substitution, becoming less sociable). Public policies seem to have difficulties in integrating these parameters into a coherent overall policy to help such people (keep them within civil society, information about rights, meeting needs).