Among the most important interstate agreements for Coloradoans are those governing water resources. Colorado participates with New Mexico in the Animas–La Plata Project, Costilla Creek, and La Plata River compacts; with Kansas in the Arkansas River Compact of 1949; and with Nebraska in the South Platte River Compact. The Cumbres and Toltec Scenic Railroad Compact supports the tourism industry. Multistate compacts allocate water from the Colorado and Republican rivers and the Rio Grande. Colorado also is a signatory to such regional agreements as the Interstate Oil and Gas Compact and the Western Interstate Energy Compact.
The Western Interstate Commission for Higher Education has its headquarters in Boulder, and the National Conference of State Legislatures has its headquarters in Denver. Federal grants to Colorado totaled over $3.9 billion in 2001.