This study was designed to investigate the pattern of obstetric morbidity and to determine the frequency of serious life-threatening episodes as a basis for clinical audit. The records of over 2,000 maternities from a National Health Service Consultant Unit during a six-month period were analysed. Morbidity was noted in almost a quarter of the cases, and life-threatening episodes, termed 'near miss' morbidity, were identified. As the maternal death rate has fallen in this country, maternal morbidity has come to represent a more useful indicator of obstetric care than mortality. The results of this study identify the need for an agreed set of definitions for 'near miss' morbidity, and suggest that not only should it be included for discussion in unit perinatal meetings, but that Regional obstetric morbidity enquiries would provide valuable denominator data on morbidity.