The vast majority of anaesthetists will be unaffected by substance abuse, but for those few that are affected the consequences can be devastating both for them and for their patients. The most immediate risk is of harm to patients: a report of drug or alcohol abuse in an anaesthetist should be taken seriously and investigated without delay. Physical or behavioural symptoms at work indicate advanced addiction. There is a danger of self-harm following intervention; plans must be made in advance to facilitate treatment and for admission to a specialist unit if necessary. The ultimate objective should always be to try and resume a normal pattern of personal and professional life.