The Snowmelt-Runoff Model (SRM) is designed to simulate and forecast daily streamflow in mountain basins where snowmelt is a major runoff factor. Most recently, it has also been applied to evaluate the effect of a changed climate on the seasonal snow cover and runoff. SRM was developed by Martinec (1975) in small European basins. Thanks to the progress of satellite remote sensing of snow cover, SRM has been applied to larger and larger basins. The Ganges River Basin in the Himalayas, the largest basin where SRM has been applied so far, is about 917,000 km2(Seidel et al., 2000). Runoff computations by SRM appear to be relatively easily understood. To date, the model has been applied by various agencies, institutes and universities in about 80 basins situated in 25 different countries. About 25% of these applications have been performed by the model developers and 75 % by independent users. SRM also successfully underwent tests by the World Meteorological Organization with regard to runoff simulations (WMO, 1986) and to partially simulated conditions of real time runoff forecasts (WMO, 1992). SRM is one of the few hydrological models developed that requires direct inputs derived from remote-sensing data.