For three years, NGA has been working with 10 states and 1 territory to develop statewide programs that transform the care of the highest-need and highest-cost Medicaid enrollees. The goal was to significantly improve outcomes while decreasing the associated health care spending. Medicaid High-Need, High-Cost Programs: Promising Practices for Evaluation Metrics presents core metrics and evaluation strategy necessary to understand if changes to state Medicaid programs are really successful with measuring impact, health outcomes and cost savings.