Read about how GRACE Follow-On mission, launched in May 2018, is engineered, once again with contributions from UTCSR, to continue the unique measurements of the mass change in the Earth system. A description of the GRACE-FO mission and flight systems description was published online on April 26, 2019 (https://arc.aiaa.org/doi/10.2514/1.A34326). This mission continues the legacy of GRACE, the US/German Gravity Recovery And Climate Experiment, that was conceived, proposed and implemented under UTCSR leadership. Since their launch in 2002, the twin GRACE satellites have revolutionized our understanding of mass transport in the Earth system using satellite derived time-variations of Earth’s gravity, as described in a review published in the April 15, 2019 issue of Nature Climate Change.