The analysis provides an updated estimate of the health, social, and economic benefits of investing in strengthening health systems to deliver RMNCH interventions in 74 lowincome and middle-income countries that account for more than 95% of maternal and child deaths. It provides a global cost estimate of the level of investment required for the integrated delivery of a set of evidence-based RMNCH interventions. In modelling investment needs and health outcomes, the analysis supports an implementation approach that factors in equity and the social determinants of health—ie, by considering the effect of conditional cash transfers on increasing the proportion of women giving birth in health facilities. While recognising the intrinsic value of health and its role in meeting basic human rights, it also attempts to estimate the economic benefits of averting morbidity and mortality. This study analyses the broader, long-term health and nutrition gains to human capital development, and the substantial benefits of family planning for both health outcomes and socioeconomic development. The framework also emphasises the broader links to, and need for, health systems strengthening