This paper, first of a 3-part series, provides an assessment of the USDA's Mississippi River Basin Healthy Watersheds Initiative (MRBI), a promising new approach to achieving cleaner water in agriculturally dominated watersheds in the United States. The initiative concentrates a portion of taxpayer-supported conservation funds in high-priority, targeted watersheds, which we found to be a better strategy than the prevailing approach of thinly dispersing funds across the rural landscape. With a few mid-course adjustments, the initiative could help achieve measurable improvements in many local streams and rivers. Our analysis and recommendations can help USDA and its many partners-state agricultural and water quality agencies, watershed groups, universities, and farm and environmental non-governmental organizations-as they strive to demonstrate environmental outcomes with ever-shrinking taxpayer funds.