Many smokers have difficulty in stopping smoking, either motivated to stop or forced for health, economic or statutory reasons. They have in common a heavy tobacco dependence and a high level of cigarette consumption. Often they combined factors impairing success in the attempt to stop smoking : e. g. anxio-depressive disorders, use of psychoactive substances, socio-economic deprivation. Smoking cessation specialists must optimize their interventions in order to improve the care of these highly dependent smokers.