The influence on the emergency caesarean section rate of 24-h supervisory staff coverage in the labour and delivery area was investigated. In period I (1978-1979), the supervisory staff were inside the hospital from 07.01 to 17.00 hours, and on call at home from 17.01 to 07.00 hours of the next day, and in period II (1980-1981), the supervisory staff were inside the hospital 24 h a day. The section rate for fetal distress increased during period II. The rate for maternal complications also increased in the 17.01-24.00 hours shift and decreased in the 07.01-17.00 hours shift during period II. However, the overall emergency caesarean section rate did not change between the two periods.