Postpartum haemorrhage (PPH) is a leading cause of maternal death. Preventing PPH can spare women from experiencing the trauma and risks of PPH, reduce the strain on overstretched health systems, and probably produce better outcomes than a strategy solely focused on PPH treatment. Prevention of PPH is often interpreted as provision of uterotonic drugs to contract the uterus at the time of childbirth. Although uterotonics are a central strategy for PPH prevention, several other approaches can prevent PPH or ameliorate its severity. These approaches include addressing the unmet need for contraception, remedying anaemia and other modifiable risk factors for PPH, optimising medical conditions that predispose to PPH, and tackling the rise in caesarean births in many countries. Effective delivery of preventive care requires early and regular antenatal care and planned birth at appropriately resourced health facilities. Social and behavioural change interventions for improving contraceptive provision and uptake, targeting adolescents, postpartum women, geographically remote communities, and families on low income, are a priority. Effective interventions to tackle anaemia include the management of heavy menstrual bleeding, pre-pregnancy or antenatal haemoglobin testing and oral or intravenous iron treatment, dietary improvements, and-on rare occasions-blood transfusion. Risk factors for PPH that need attention include high BMI, multiple pregnancy, gestational diabetes, pre-eclampsia, macrosomia, and several medical conditions. Caesarean births are associated with a substantial increase in PPH risk and should therefore only be done when medically indicated. A Cochrane network meta-analysis of 122 trials, with 121 931 women, found that the combinations of oxytocin plus misoprostol, or oxytocin plus ergometrine, were the most effective prophylaxis for PPH when given at the time of childbirth; however, these combinations had a higher risk of side-effects compared with single-drug prophylaxis. Oxytocin and carbetocin were the most effective single drugs for PPH prophylaxis, with minimal side-effects. Single uterotonic prophylaxis with either oxytocin or carbetocin is, therefore, recommended for routine prophylaxis. However, if oxytocin or carbetocin is not accessible, misoprostol is an alternative. Combination prophylaxis with oxytocin plus misoprostol can be considered for women at high risk of PPH. Ergometrine alone and oxytocin plus ergometrine combination are no longer recommended due to hypertension-related safety concerns. A robust implementation approach that engages various stakeholders to promote change, ensures the supply of quality-assured medicines and devices, provides training and support, and secures ongoing political and financial commitment is necessary to translate evidence into global impact.