The Norwegian Government has decided that an interprofessional co-operation group should be established in all municipalities as from 1988. The purpose of the co-operation groups is to improve rehabilitation of patients with long-term sickness certification. The aim of the survey was to describe the establishment and function of the co-operation groups as per 1/7 1988. The local national insurance offices reported that 88% of the municipalities had started a co-operation group and 63% had held meetings. The co-operation groups were most effective in small municipalities. Activity was low in the larger towns.