One hundred ten patients addicted to nicotine were subjected to either sudden or gradual withdrawal in the course of a smoking cessation programme. Eighty-two patients emerged from the treatment as non-smokers. In a follow-up after 1 year 70% of these successful clients replied to an anonymous questionnaire. Concerning the relapse rate, no significant difference could be found between the two treatment groups, but patients who underwent slow withdrawal smoked significantly less when comparing their current consumption with that before the start of the therapy. Patients who underwent sudden stopping reached their original level of nicotine use again.