The Baron LIS NOAH-R distributed hydrological modeling system represents an integration of several major technologies, including those of the NASA Land-Information, the NOAH LSM, and various routing methodologies developed by the authors. In this talk, the authors will describe the modeling system and then discuss its application to one or more US basins. Comparisons against observations for both short and long term simulation periods will be presented, as well as strategies for model calibration. Methods for data-assimilation and their application will also be briefly described in the context of operational use in a decision-support context.