Summary o 1. It is essential to investigate all cases of pyrexia in the pueperium at the earliest possible moment. 2. If infection is shown to be due to Str. pyogenes it is essential to attempt to trace it to its probable source. 3. Education of attendants to report colds or sore throats with a view to exclusion of Str. pyogenes is essential. 4. The criteria demanded before engagement of midwives and employees in maternity homes are discussed. 5. A brief classification of beta haemolytic streptococci has been included as an aid to interpretation of reports and the methods of bacteriological examination in puerperal sepsis have been indicated.