The Indian Health Service (IHS) within the Department of Health and Human Services (HHS) is the lead federal agency charged with improving the health of American Indians and Alaska Natives. It aims to do so by providing health services either directly or through contracts or compacts with Indian Tribes (ITs) and Tribal Organizations (TOs). This book provides an overview of the Indian Health Service. It also discusses the opportunities that may be available to help improve the contract health services program; the impact of the Affordable Care Act on IHS; and the Indian Health Care Improvement Act.