As the current global COVID-19 pandemic makes clear, data are power. Now more than ever it is important to reflect on who holds that power and how well it is used to improve global health. This was also on the minds of a group of global health experts at the onset of the Sustainable Development Goals (SDGs). In 2015, after a first meeting in Kirkland, USA, these experts delivered a call to action for a robust maternal, newborn and child health (MNCH) measurement system that could effectively measure and monitor the coverage of high-impact healthcare while also improving capacity to track universal health coverage for women and children. That call to action defined five principles: (1) a core focus on a set of indicators; (2) data relevant to countries; (3) measurement innovations; (4) embedded equity analysis and (5) global leadership.