Both sex and gender matter to health, yet both are frequently ignored, overlooked or misunderstood in health policies, programmes and practices. In this talk I will use COVID-19 as an example to explore the influence that sex and gender exert in driving health inequities. Data will be drawn from our global COVID-19 sex-disaggregated tracker, and reasons to explain differences in health outcomes seen in men and women will be outlined. The talk will also touch on evidence for how the global health system currently responds to sex and gender, and how it could do better in the future in order to improve the health of everyone.