When reviewing clinical research on delusional depression published since 1999 the following results have emerged: (1) Mood-congruent delusions are indicators of severity of depressive episodes. (2) Among the new generation antidepressants fluvoxamine has a hgh response rate (79%) in patients with mood-congruent delusional major depression. (3) Among the new generation (atypical) antipsychotics neither risperidone nor quetiapine has been found effective. (4) However, quetiapine has been found effective in schizoaffective disorder. This is in agreement with research on cognitive functioning which has placed schizoaffective disorders closer to schizophrenia than to mood disorders.