Tribal Self-Governance Demonstration Project Act

Tribal Self-Governance Demonstration Project Act - Amends the Indian Self-Determination and Education Assistance Act to extend the Tribal Self-Governance Demonstration Project from five to eight years.

Increases the number of participating tribes in the project from 20 to 30.

Directs the Secretary of the Interior (Secretary) to negotiate and enter into an annual written funding agreement with the governing body of a participating tribal government that successfully completes its Self-Governance Planning Grant.

Authorizes appropriations for the ten tribes added to the Project by this Act.

Authorizes such participating tribes to administer all programs, services, and functions of the Department of the Interior that are otherwise available to Indian tribes or Indians.

Authorizes the Secretary to study and report to the Congress on the feasibility of including certain programs and activities in the Project that are currently excluded by Federal law.

Removes the statutory requirement that the Secretary approve attorney and other professional contracts of the participating Indian tribal governments operating under the Project.

Directs the Secretary to interpret Federal laws and regulations in a manner that will facilitate the inclusion of activities, programs, services, and functions in the agreements authorized by this Act.

Requires the Secretary of Health and Human Services to study and report to the Congress on the feasibility of extending such Project to the activities, programs, functions, and services of the Indian Health Service.