Football is the most popular spectator sport in the United States, and with annual revenues topping $8 billion the National Football League is the country's wealthiest professional sports organization. But the league was on the defensive during the 2009-2010 season because of a jarring debate over its alleged indifference toward player safety and health. Medical research now indicates a connection between concussions that players routinely suffer during games and long-term brain disease, including dementia. Under pressure from the NFL Players Association, news media and Congress, the NFL is belatedly acknowledging a possible link and trying to minimize the risk to players by, among other changes, limiting a player's return to the game after a concussion. Despite football's popularity, the NFL is also facing economic difficulties. Attendance sagged during the 2009-2010 season, the future of lucrative TV contracts is cloudy and the league and the players' union start out far apart as negotiations begin for a new collective-bargaining agreement.

Kenneth Jost is Supreme Court editor, CQ Press; associate editor, CQ Researcher; and author of The Supreme Court Yearbook since the 1992-1993 edition.