The outcome of a psychoeducational treatment programme for very early-onset schizophrenics was compared with a standard reference treatment. The study sample consisted of 12 patients in each group. Clinical outcome was assessed by relapses during the 2-year treatment period and changes in psychosocial functioning as measured by the Global Assessment Scale. A cost-effectiveness analysis was also carried out. The results indicated that the most effective programme measured by relapse was also the cheapest: the psychoeducational programme. Patients with poor premorbid psychosocial functioning benefit most from this treatment. Decisive with respect to how effective the programme can be is the cooperativeness of patients' parents and their ability to change their emotional attitudes toward the patient.