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Nearly the whole Antarctic ice sheet, including the attached ice shelves, shows a net accumulation. Factors other than precipitation influence the budget only to a small degree. In the inner parts of the ice sheet it is frequently difficult to establish the annual accumulation. Determinations by isotope frequency do not always agree with those derived from stratigraphic evidence. A mean accumulation of 15cm water equivalent corresponding to 1900gt/year (1 gt=1 gigaton=1km^3 water) is rather on the low side. The loss by runoff of meltwater or by evaporation in the border regions of prevailing ablation is small, 10gt/year. The open ice sheet moves slowly; the ice loss is 50gt/year. Glaciers move with varying speeds; an estimate of 520gt/year from glaciers and ice streams is rather high. Ice shelves surround one-half of the continent. A high estimate gives 880gt as their productivity. Some melting will occur at the bottom of the floating ice shelves and glaciers. The amount is not well known; it is estimated at 200gt/year but will hardly exceed 300gt/year. With a total loss of 1660gt/year the final balance is slightly positive. In view of the uncertainties, gain and loss might be equal, but the budget will not be markedly negative. With the ice sheets of Antarctica and Greenland in balance, the present rise of sea level can be caused by the mass loss of the mountain glaciers combined with a warming of the ocean.