The Indian Health Service (IHS), an agency within the Department of Health and Human Services, is responsible for providing federal health services to American Indians and Alaska Natives. The provision of health services to members of federally-recognized Tribes grew out of the special government-to-government relationship between the federal government and Indian Tribes. The IHS is the principal federal health care provider and health advocate for Indian people, and provides a comprehensive health service delivery system for American Indians and Alaska Natives. The IHS Mission is to raise the physical, mental, social, and spiritual health of American Indians and Alaska Natives to the highest level.