The Indian Health Service (IHS) is an agency in the Department of Health and Human Services (HHS) that provides health care to American Indians and Alaska Natives. When care at an IHS-funded facility is unavailable, IHS's Contract Health Service (CHS) program pays for care from non-IHS providers if the patient meets certain requirements and funding is available. The Patient Protection and Affordable Care Act requires the Government Accountability Office (GAO) to study the administration of the CHS program, including a focus on the allocation of funds. IHS uses three primary methods to determine the allocation of CHS funds to the 12 IHS geographic area offices: base funding, which accounts for most of the allocation; annual adjustments; and program increases, which are provided to expand the CHS program. This book examines (1) the extent to which IHS's allocation of CHS funding varied across IHS areas, and (2) what steps IHS has taken to address funding variation within the CHS program.