This study, conducted under a subcontract to Econometrica, Inc., examined the feasibility and potential cost implications of the Navajo Nation operating its own independent Medicaid agency. The Navajo Nation has a population of nearly 300,000 and a land base of more than 26,649 square miles within the States of Arizona, New Mexico, and Utah. Under the Indian Health Care Improvement Act provisions of the Affordable Care Act, the Department of Health and Human Services was mandated to conduct a study of the feasibility of a Navajo Medicaid Agency to serve all American Indians and Alaska Natives living within the boundaries of the Navajo Nation and to submit a Report to Congress on the findings of the study. The project team was responsible for meeting with the Navajo Nation Tribal leadership and the Navajo Nation Department of Health to discuss the project and secure demographic data, as well as with the States of Arizona, New Mexico, and Utah to obtain data on the eligibility requirements, covered services, number of American Indians enrolled in Medicaid who reside within the boundaries of the Navajo Reservation, per capita Medicaid costs for American Indians enrolled in Medicaid, and sites of care for services provided to AI enrolled in Medicaid in each State. The statutory requirements for providing Medicaid coverage for all Medicaid applicants or recipients within the Reservation boundaries were identified and alternative options for addressing the issue of multiple-State benefit packages were explored. Our work under this contract included developing an estimation methodology that was used for projecting enrollment, service utilization by site, administrative costs, and claims costs that would be associated with the Navajo Nation Medicaid Agency; calculating a Federal Medical Assistance Percentage (FMAP) for the Navajo Medicaid Agency; and analyzing the potential impact of the Navajo Medicaid Agency on enrollment levels, Medicaid costs, and FMAPs for the three affected States. The project team then worked closely with the Centers for Medicare & Medicaid Services (CMS) to prepare the Report to Congress on the Feasibility of a Navajo Medicaid Agency, which CMS finalized and submitted to Congress on June 14, 2014.