Background: In past decades clinicians have increasingly recognized the importance of psychological support for people with diabetes and their families, and many have recommended integrating psychological counselling into routine diabetes care. It is therefore important to consider whether psychological interventions in diabetes are effective in improving clinical outcomes. Methods: This review was limited to the literature reporting on the treatment of five common psychological problems known to complicate diabetes management: depression, eating disorders, anxiety/stress, self-destructive behaviour and interpersonal/family conflicts. A literature search was undertaken using MedLine and PsychInfo, including studies published in English peer-reviewed journals between 1990 and 2001, reporting on the effects of psychological interventions in the areas mentioned. Case studies were excluded from the review. Results: In line with earlier reviews, relatively little empirical research was found to substantiate the effect of psychological counselling in complicated diabetes. Most studies are uncontrolled, and involve small samples. In total only 11 randomized controlled trials were identified. Results indicate that cognitive behaviour therapy (CBT) is effective in the treatment of depression in Type 2 diabetes patients, both in reducing depressive symptoms and HbA1c. Favourable effects have been observed in pilot studies applying CBT in the field of stress management, eating disorders and self-destructive behaviour, but future research should substantiate these preliminary findings. Behaviour family therapy proved beneficial in terms of resolving family conflicts, but did not impact glycaemic control. Conclusions: Evidence to support the effect of psychological treatment in problematic diabetes is still scarce, due to limited research in this area. Suggestions are made to further develop psychotherapeutic research in diabetes care. We conclude that future research should gain from a behavioural medicine approach to diabetes, with close collaboration between diabetologists and psychologists.