This chapter includes significant literature underpinning the causes, initial and advanced management, investigation and aftercare required when a woman loses more than 500mL of blood at the time of birth. This common, but life-threatening, obstetric emergency is described including recent pivotal publications in the field. Key learning points: Understand prevention, causes and treatment of major postpartum haemorrhage (PPH). Understand the effect of antenatal anaemia on PPH. Early recognition of PPH and prompt systematic management remain cornerstones of effective care. Always aim to measure or weigh, rather than estimate, blood loss, where possible. Prioritise early fluid resuscitation: intravenous fluid (and blood transfusion if required) should not be delayed because of false reassurance from a single haemoglobin result. Escalate to senior team members of the multi-professional team. Give tranexamic acid early, alongside uterotonics. Consider the use of cell salvage and point-of-care clotting assessment. Consider early hysterectomy, if medical and surgical interventions are ineffective. Document details of management and post PPH care accurately and clearly.