 - The subjects must fulfil schizophrenia criteria both according to DSM- IV 295.10, .20, .30, .60, .90 American Psychiatric association and the Research Diagnostic Criteria for schizophrenia RDC 40. They must also have at least mild residual symptoms CGI 3 points. The DSM-IV diagnosis will be verified by use of the SCID-I 41. The DSM-IV is clearly the most commonly used in psychiatric research, so this is important to be able to generalize the findings. However, several previous studies have used the RDC, so to be able to compare the results, we will diagnose the patients according to both systems. 