The National Railroad Passenger Corporation, doing business as Amtrak , is a quasi-governmental corporation that was organized on May 1 1971, to provide intercity passenger train service in the United States. "Amtrak" is a portmanteau of the words "American" and "track".

All of Amtrak's preferred stock is owned by the U.S. federal government. The members of its board of directors are appointed by the president of the United States and are subject to confirmation by the United States Senate. Common stock was issued in 1971 to railroads that contributed capital and equipment; its current holders consider the stock to be worthless but declined a 2002 buy-out offer by Amtrak.

Amtrak employs nearly 19,000 people. It operates passenger service on 21,000 miles (33,800 km) of track primarily owned by other railroads connecting 500 destinations in 46 states. Some routes serve Canada. In fiscal year 2006, Amtrak served 24.3 million passengers, a company record. According to estimates for fiscal year 2007, Amtrak has served over the 25 million passenger mark, a 6% increase from the previous year.