Although obstetric complications are sometimes presented as a relatively easy alternative to maternal deaths, difficulties remain in their definition and identification, and there is limited experience with the use of severe obstetric complications as a starting point for audits or case reviews or as an indicator for monitoring the success of safe motherhood programmes in low-income countries. In this paper we review published studies reporting on the measurement of severe acute maternal morbidity in low-income countries. We found 37 studies from 24 countries. We describe the definition and ascertainment of cases of severe acute maternal morbidity and we give examples of how information on severe acute maternal morbidity has been used to inform safe motherhood programmes in low-income countries.