We studied unintentional paediatric eucalyptus oil poisoning to identify potential intervention strategies. The epidemiology of paediatric eucalyptus oil poisoning in Victoria was determined by analysis of four databases. The sequence of events preceding ingestion was examined by a telephone survey involving 109 parents or guardians of children under five years involved in an actual or suspected ingestion of eucalyptus oil. Such children were identified prospectively from all callers during a nine-month period to the Victorian Poisons Information Centre and those presenting to the emergency departments of the participating hospitals of the Victorian Injury Surveillance System. Eucalyptus oil was a leading agent associated with hospitalisation for poisoning among Victorian children aged under five years. In the telephone survey, 90 incidents were found to involve vaporiser solutions, 15 eucalyptus oil preparations, and the remainder other eucalyptus-oil-containing products of a medicinal nature. Regardless of the type of product, 74 per cent gained access via a home vaporiser unit, most frequently placed at ground level. Although amounts ingested are usually small, the reported range of toxic doses is wide, necessitating at least a medical assessment following ingestion. Potential countermeasures identified in a consultative workshop included: discontinuing the use of eucalyptus oil as a therapeutic agent; confirmation that vaporiser-well residues are nontoxic; removal of barriers to product reregistration following safety-related modifications; improved child-resistant closures; discouraging vaporiser use for respiratory infections among young children; and development and dissemination of protocols for treatment of suspected ingestion.