In the central Namib desert (Namibia) the subterranean termite Psammotermes allocerus (Silvestri)(Isoptera: Rhinotermitidae) builds its nest structures nearly 30cm deep into the dry sand of the Kuiseb river. Gallery systems protect the insects against unfavourable climatic conditions and reduce body-water loss occuring in all humidities below 98% relative humidity. Furthermore the social structure of a termite colony contributes essentially to a reduction of individual water loss in subsaturated atmospheres as well as to more efficient water uptake. Water vapour uptake from the atmosphere is not possible and free liquid water cannot be used as a water resource because of the strong surface tension of the water droplets. However , with the aid of their hypopharynx pseudergates P.allocerus are able to extract water from the capillary system of loamy sand. The role of 'water sacs' in connection with water uptake and storage is still unknown. Keywords: Termites, waterbalance, social effects, water vapour absorption, hypopharynx, Namibia.