All consecutively admitted patients suffering from paranoid psychoses and admitted to the Department of Psychiatry, University of Oslo, during two defined periods (1946-1948 and 1958-1961) have been personally followed up by the author after 5-18 years and by Stein Opjordsmoen after 22-39 years. After the first follow-up period 65% were without psychotic symptoms, after the last period 44%. According to Scandinavian diagnostic tradition, there is a gradual shift from very good clinical and social outcome for patients with reactive psychoses to very poor outcome for schizophrenics, patients with schizophreniform psychoses being in between. According to the DSM-III system, patients with affective and schizoaffective psychoses score best, followed by those with paranoid and schizophreniform disorders. Those with schizophrenia score worst. Course and outcome are primarily dependent on the diagnostic category, not the type of delusion. Of the patients with Kraepelin's paranoia, about one-third were without psychotic symptoms at last follow-up.