The headwaters of the Columbia and Missouri Rivers originate in Montana, making this a prime location for the study of large river systems.  In addition to their ecological importance, supplying habitats for hundreds of species, these two rivers have significant economic impacts, providing the means to transport goods and making 25% of the electricity for the Northwest available via hydroelectric dams.  With multiple conditions and scales, from mountain stream headwaters to large dammed reservoirs, a broad spectrum of large river issues are being examined including responses to climate change and human modification.  Support for this focus area is forging new academic and technological partnerships, through competitive faculty hires, integrated and cross-disciplinary programs, and graduate and undergraduate training, all aimed at laying the foundation for significant future development of a major scientific river center.