The report concerns an outbreak of neonatal Klebsiella septicaemia at the University College Hospital, Ibadan, Nigeria, between October and November 1991. Mortality, 35.7%, was higher in the preterm babies than in the term babies (p < 0.05). The important predisposing factors to infection identified were birth asphyxia, necessitating active resuscitation, prematurity, prolonged rupture of the membranes and maternal intrapartum pyrexia. The Klebsiella species isolated from the babies and the hospital environment during the outbreak were of the multiple drug resistant type. Preventive measures and the need for a continual bacteriological surveillance are highlighted.