Improvements in neonatal care have resulted in a downward shift of the viability threshold for preterm babies. In general, the lower the gestational age and birth weight at delivery, the higher the chance of mortality and morbidity. Some may argue that the softer cranium and vulnerable brain of the extremely low-birth-weight baby should not be exposed to the ‘stresses’ of vaginal birth. In this article we briefly discuss the difficulties in decision making surrounding the lowest thresholds of viability and examine what the literature has to say regarding route of delivery. It is important that parents only make these difficult decisions after being fully informed of the likely short- and long-term outcomes. With regard to route of delivery we conclude that in the absence of an obstetric indication there is no clear evidence to support performing a caesarean delivery.