This study set out to compare the time required to be ready for emergency caesarean section using spinal or general anaesthesia. The time for surgical readiness was taken as the time from leaving the delivery room to the time of skin incision. We conducted a retrospective, observational survey in an obstetric tertiary referral hospital delivering over 3000 patients per annum. The notes were obtainable for 137 women who had been delivered by emergency caesarean section using either spinal or general anaesthesia between 1st January 2000 and 31st December 2000. The mean time for surgical readiness was 15.4 min [range 2-44 min] for general versus 27.6 min [range 1355 min] for spinal anaesthesia (t test: P < 0.01). In this series the proportion of patients falling outside the thirty-minute standard counting only surgical readiness was 31% for the spinal and 12% for the general anaesthesia group (chi(2) with Yates' correction: P < 0.05). The thirty-minute audit standard is often unrealistic and unnecessary and has little evidence to support its continued use. The new classification of clinical urgency of caesarean section endorsed by the Royal College of Obstetricians and Gynaecologists may clarify those few cases where it is appropriate. The huge reduction in maternal mortality directly due to anaesthesia achieved over the last 30 years must not be compromised in the pursuit of an arbitrary time limit. (C) 2003 Published by Elsevier Science Ltd.