Objectives. The effectiveness of a cognitive and a behavioural treatment for obese binge eaters and obese non-binge eaters was evaluated at I-year follow-up. Furthermore, we examined the role of weight changes on psychological well-being at I-year follow-up. Design and method. Participants were reassessed 6 months and I year after they had finished a group cognitive treatment or a group behavioural treatment. The outcome measures were; psychological well-being (concerns about shape, weight and eating, self-esteem and depression), binge eating, and weight. Results and conclusions. Analyses on the completers' sample revealed that both treatments had a markedly positive and lasting impact on shape concern, weight concern and eating concern, binge eating, self-esteem, and depression at 1-year followup. Cognitive treatment was not superior to behavioural treatment on most outcome measures. This might be due to selective drop-out, Analyses including non-responders showed that the cognitive treatment was superior on shape, weight and eating concern, and binge eating. The I-year follow-up results for weight-loss were disappointing. Between pre-treatment and 1-year follow-up participants in the behaviour treatment lost 3.0 kg, while participants in the cognitive treatment lost 0.3 kg. However, participants who gained weight were as successful on changes in psychological well-being changes as participants who lost weight.