In 2025, California, Washington, and Oregon formed the West Coast Health Alliance through an interstate compact, responding to concerns about federal public health leadership. The compact allows the three states to coordinate health policy and share resources during emergencies. Also in 2025, 30 states joined the Interstate Licensure Compact for Social Work, while states continued advancing legislation to join physical therapy and occupational therapy compacts. The National Popular Vote Interstate Compact reached 209 electoral votes across 17 states and Washington D.C., still short of the 270 needed to take effect.
Article I, Section 10, Clause 3 requires states to obtain congressional consent before entering agreements or compacts with other states. However, the Supreme Court has ruled that only compacts increasing state political power while undermining federal authority require approval. Most modern compacts address practical coordination issues like professional licensing, resource sharing, or regional cooperation. States use compacts to solve problems that cross state lines but don''t require federal intervention. Recent growth in licensing compacts reflects workforce mobility demands, while policy compacts show states collaborating on issues where they distrust federal action.