On the basis of first principles, anaphylaxis to a vaccine or vaccine component is a contraindication to future receipt of that vaccine. • On the basis of strong evidence, live viral vaccines should not be administered to severely immunocompromised children. • On the basis of some evidence with consensus, children with egg allergies may receive inactivated influenza vaccine. • On the basis of strong evidence, neither measles-mumps-rubella vaccine nor thimerosal causes autism. • On the basis of some evidence with consensus, alternative vaccination schedules have no benefit and receipt of human papillomavirus vaccines does not result in promiscuity. • On the basis of first principles and consensus, vaccine risk communication requires a tailored approach to each individual family.