To re-evaluate the recommendations for MMR-vaccination of children known to be allergic to eggs a descriptive study was carried out in which all reported allergic side effects for 1987-1996 were studied. During the 10 year period 1,200,000 MMR vaccinations were given. Eighteen were found with immediate type hypertensity, but only eight presented symptoms within 24 hours. One child with egg-allergy reacted within 15 min presenting rhinitis and respiratory difficulty. None had anaphylactic shock. It was concluded that MMR vaccine may be administered to children allergic to eggs when given in a paediatric ward where appropriate emergency treatment is available.