In the field, glaciologists assess the health of glaciers by combining direct observations with cutting-edge technology. Mass balance, a key indicator, compares winter snow accumulation with summer melt using markers drilled into the ice. Cameras track the movement of the glacier fronts, whilst lidar and GPS surveys scan the glacier in 3D to quantify its changes. This data, collected year after year, helps us understand glacial dynamics and anticipate their future in the face of climate change. While the terrain sparks the imagination, it represents only a fraction of the work: the bulk of the work then takes place in the laboratory and the office, analysing data, graphs and measurement series to understand and anticipate the future of the glaciers.