On 13 and 14 March CERN hosted an international workshop on atom interferometry and the prospects for future large-scale experiments employing this quantum-sensing technique. This quantum sensing technology holds great promise for making ultra-sensitive measurements in fundamental physics. Like light interferometry, atom interferometry involves measuring interference patterns, but between atomic wave packets rather than light waves. Although the potential of atom interferometers for fundamental scientific measurements was the principal focus of the meeting, it was also emphasised that technologies based on the same principles also have wide-ranging practical applications. These include gravimetry, geodesy, navigation, time-keeping and Earth observation from space, providing, for example, a novel and sensitive technique for monitoring the effects of climate change through measurements of the Earth’s gravitational field.