OBJECTIVE To identify prognostic factors to outpatient alcohol treatment on admission as well as during the treatment period. METHODS A cohort study of n = 209 alcoholic patients (DSM-IV) during 6 months of outpatient treatment. Eight medical doctors from two hospitals were involved. Co-responsible participation in treatment was a necessary condition. At admission, we documented socio demographic factors, use of other drugs and severity of alcohol consumption. During the 6 months, we observed medication for prevention of alcohol relapse [disulfiram (DIS), acamprosate], number of sessions with the doctor, number of phases of the consultation and medication for depression. Primary outcome variables were time to first heavy relapse and abstinence of heavy alcohol consumption. These were measured with Timeline Followback. Five or more alcohol units of 10 g in one relapse day were considered heavy relapse. RESULTS The patients were 84% males, with 41 years median age; the median alcohol consumption was 192 g per day with a median duration of 13 years of heavy consumption. The median education was 6 years with 61% of the patients from lower socio-economic levels. The Kaplan-Meier heavy relapse rate at 6 months was 23%. On admission to treatment, female gender, lower socio-economic levels, cocaine use, >20 years of consumption, gamma glutamyl transferase values above normal and five or more alcohol-related problems on the Alcohol-Related Problem Questionnaire predicted worse outcomes. Having a full-time job and shorter abstinence time before treatment (until 7 days) predicted better outcomes. During the 6 months, we found that DIS for <120 days was a prognostic factor of worse outcomes. DIS for at least 120 days, >50% of adherence to consultations and more than two phases on each consultation predicted better outcomes. The combined sensitivity and specificity for DIS for at least 120 days, >50% of adherence to consultations and more than two phases on consultation regarding abstinence from heavy relapse were respectively 100 and 71%. CONCLUSIONS During 6 months of outpatient treatment, longer adherence to DIS and consultations as well as more phases in a consultation involving necessarily a co-responsible predict a good outcome independently of the patient features at admission.