The purpose of this study is to determine if and to what extend a composite measure of treatment motivation and behavior change motivation predicts alcohol treatment success. It is expected that the composite measure based on the stages of the Transtheoretical Model of Behavior Change is a better predictor for treatment outcome than treatment motivation or behavior change motivation alone. Participants will be recruited from alcohol treatment centers. A baseline interview regarding their motivation, drinking behavior and personal treatment goals will be conducted. At the end of treatment, treatment staff will be asked about treatment involvement of each participant. Two follow-up interviews will be conducted after 6 and 12 months. To identify the impact of behavior change and treatment motivation on change in drinking behavior, data will be pooled with a non-treatment seeking sample. Conclusions can be drawn on what motivation pattern best predicts behavior change for those utilizing formal help and for those remitting without formal help (self-changers).