Ankyloglossia (tongue tie) in the neonate can be a cause of breastfeeding problems. Frenotomy (cutting of the frenulum linguae) had fallen into disrepute, but has regained its place as a standard medical procedure in Anglo-Saxon countries, though not in the Netherlands. We present two neonates, both boys, presenting with breastfeeding problems caused by ankyloglossia. The first baby described did not drink enough and hence did not gain any weight. The mother of the second patient experienced a great deal of pain and had cracked nipples, caused by an abnormal suckling action. Both boys underwent frenotomy with good result. Recent ultrasound studies reveal that frenotomy immediately normalizes the suckling action in babies with ankyloglossia. Randomized controlled trials show that 95% of breastfeeding problems disappear. There is sufficient evidence to state that frenotomy is a very safe and useful procedure in neonates.