Obesity in children is difficult to treat, but it seems to be easier to treat than adult obesity. The first step in treatment is to identify effective advice relating to nutrition and physical activity. In most treatment studies the macronutrient composition of the diet is not of major importance for treatment outcome. In relation to physical activity fat-utilisation strategies have been described. The second step includes appropriate approaches to lifestyle change. In Europe there are no drugs approved for children, and surgery for children is still limited to research projects. Thus, the major challenge is to develop effective ways of changing lifestyle. Family therapy may be an effective approach in preventing severe obesity from developing during puberty, and a therapeutic strategy based on treatment studies is described. The family-therapy techniques used here are intended to facilitate the family's own attempts to modify their lifestyle, and to increase their own sense of responsibility and readiness to change, i.e. these variables are the prime targets during therapy. Thus, the family, not the therapist, assumes responsibility for the changes achieved. This approach may be helpful in making the therapeutic process less cumbersome for the therapist. Instead of the therapist attempting to persuade the obese subjects to lose weight, it might be more effective to teach them to control their eating patterns through their own efforts. The treatment model includes structural family therapy and solution-focused-brief therapy. The use of such a model makes it possible to train therapists and health professionals to use an evidence-based intervention model.