The right to the highest attainable standard of health and the relevance of healthy populations in achieving sustainable development are undeniable. In the ICPD Programme of Action, Member States recognized that reproductive rights embrace existing human rights and that sexual and reproductive health and rights are central to health, well-being and to development. Aggregate gains in sexual and reproductive health and rights (SRHR) over the last two decades underscore the accuracy of that consensus. However, marked disparities persist across and within regions, with many countries exhibiting progress among households in the upper wealth quintiles, while progress remains flat or marginal among poor households. This Issue Brief highlights the inequalities inherent in a development model that continues to leave many behind and underscores the near impossibility of realizing health for all and universal access to SRHR without sustained attention to strengthening the reach, comprehensiveness, and quality of health systems.