Charles Swithinbank (1926-), glaciologist and polar explorer, first visited the Antarctic as a member of the Norwegian-British-Swedish Antarctic Expedition 1949-52. Overall he has spent three winters and twenty field seasons in the polar regions, many of them involved with international expeditions. By repeated surveying of stakes and by deploying seismic sounding equipment, he made some of the earliest estimates ofthe ‘mass balance’ of glaciers and ice sheets. Most of his career was spent at either the Scott Polar Research Institute or the British Antarctic Survey, where he was Head of Earth Sciences. He has six geographic features named for him in Antarctica. Since retiring he has continued to work on interpretation of satellite images, mapping, the use of ice runways for transport aircraft and Mars exploration.