The Passenger Rail Investment and Improvement Act of 2008 (orinally H.R. 6003, passed as division B of Pub.L. 110–432 (text) (pdf)) is a law that reauthorized Amtrak and authorized the United States Department of Transportation to provide grants for operating costs and capital expenses and to repay Amtrak's long-term debt and capital leases. It required Amtrak to adopt cost and performance metrics with regard to its intercity trains and established the Northeast Corridor Commission to govern Amtrak’s shared services along the Northeast Corridor.