• In a double-blind trial of six months' duration, a very high dose (VHD) regimen of fluphenazine decanoate (250 mg weekly) was compared with a standard dose (SD) regimen (12.5 mg weekly) in 50 chronic schizophrenic patients. The rating scales used included the Brief Psychiatric Rating Scale¹ and the Wing Ward Behavior Scale.² Both treatment groups improved during the trial, but there was no significant difference between them. The VHD regimen, however, exerted better control of the psychosis in that it had fewer patient dropouts and fewer "additional treatments" prescribed. Some of the patients receiving standard doses were probably not receiving adequate antipsychotic drug dosage. No predictors of clinical response could be defined. Extrapyramidal side effects were not significantly higher in the VHD group.