Tongue tie or ankyloglossia is a congenital variation characterised by a short lingual frenulum which may result in restriction of tongue movement and thus impact on function. Tongue tie division (frenotomy) in affected infants with breastfeeding problems yields objective improvements in milk production and breastfeeding characteristics, including objective scoring measures, weight gain and reductions in maternal pain. For the majority of mothers, frenotomy appears to enhance maintenance of breastfeeding. Tongue tie division is a safe procedure with minimal complications. The commonest complication is minor bleeding. Recurrence leading to redivision occurs with rates of 0.003-13% reported; this appears to be more common with posterior than anterior ties. There are limited reports indicating that prophylactic frenotomy may promote subsequent speech development; however, evidence is currently insufficient to condone this practice and further good quality research into this area is warranted.