Background: In a health-care service with the emphasis on improvement related to functioning and well-being, the communication process between patient and professionals is essential. There is a lack of research on this matter.

Aim: The aim was to investigate, in a group of severely mentally ill persons, whether the use of a simple communication tool could influence the sense of empowerment, satisfaction with care, therapeutic alliance and unmet needs.

Method: The study had a cluster randomized design. The intervention was a communication tool (2-COM) applied in two teams during one year. In a comparison group of two other teams, the treatment was as usual. At baseline, after six months, and after one year, assessments were made.

Results: After one year the 2-COM groups seemed to have a larger reduction in unmet needs compared to the treatment-as-usual group. However, there were large problems with attrition in the study, and it was not possible to draw relevant conclusions.

Conclusions: The methodological problems were substantial, and the study may be considered as a pilot study. In a main study the researchers ought to take control over the selection of patients on the basis of the experiences from this study.