A large sample of first-admitted hospitalized patients with delusional psychoses were personally followed up after a mean of 10 and 30 years. At last follow-up 42% showed good overall functioning and 44% were in ordinary work. Patients with affective disorder according to DSM-III had most homogeneous and favorable outcome, while a striking heterogeneity of outcome was noticed in schizophrenia, schizophreniform and paranoid disorder. Along with other reports the study showed that precipitating events indicated favorable prognosis for patients with schizophreniform, schizoaffective and paranoid disorder. Moreover, in the total sample the findings indicated that short duration of symptoms prior to admission was a good prognostic sign, indicating that early intervention is important for delusional patients.