We puropose a simplified method for external drainage of subdural effusions in infants, not calling for a second operation to remove the catheters. This method allows the daily control of evacuated fluid, guarantees smooth and uninterrupted drainage, and permits analysis of the subdural collection. This operation which we would like to call external controlled drainage, does not call for parenteral feeding, but demands paediatric and neurosurgical collaboration. The method has no pretensions other than being simple, easy, and safe.