Most countries have active vaccination programmes for children aged two months and older. It is likely that many children presenting for medical procedures which require general anaesthesia have been vaccinated recently. Although there is no evidence suggesting increased risks associated with anaesthetizing recently vaccinated children there are many theoretical reasons why this situation needs critical assessment and review. After vaccination there is local swelling and pain at the site of the injection and the most common side effects seen are fever, malaise, headache, rash and myalgia which may last from one day to three weeks. Anaesthesia, stress and trauma are known to suppress the immune system. It is suggested that if possible, children should not be subjected to anaesthesia for elective procedures within two to three weeks after vaccination. Urgent procedures should be managed according to anaesthetic principles which will minimize the effect of anaesthesia on the physiological system affected by the immunization process at the time. Paediatric anaesthesia risk management programmes should include vaccination data to enable the risks of anaesthesia in recently vaccinated children to be analysed.