James Chadwick Pennington (born June 26, 1976) is an American former professional football quarterback who played in the National Football League (NFL) for 11 seasons. He played college football for the Marshall Thundering Herd, winning the Sammy Baugh Trophy as a senior, and was selected by the New York Jets in the first round of the 2000 NFL draft. Pennington spent his first eight seasons with the Jets and was a member of the Miami Dolphins in his last three.

During his career, Pennington led the league twice in completion percentage and once in passer rating. He helped clinch a division title with the Jets in 2002 and the Dolphins in 2008, both of which are the most recent for either franchise, as well as the only times from 2001 to 2019 that the AFC East was not won by Tom Brady and the New England Patriots. Pennington was also the first player to win NFL Comeback Player of the Year multiple times, receiving the award in 2006 and 2008. At the time of his retirement, he held the NFL record for completion percentage. Since 2018, he has served as the head football coach of the Sayre School in Lexington, Kentucky.

Pennington is a native of Tennessee. His father, Elwood, was a physical education teacher and football coach at Halls High School, and his mother, Denise, a teacher at the Webb School of Knoxville, both in Knoxville. Both of Pennington's parents are of English descent. Pennington's first sport was basketball, which he began playing in the third grade. He began playing football in his freshman year in high school. His parents decided to have him repeat the eighth grade when he was enrolled at the Webb School of Knoxville due to the school's intense academic program. He played basketball and football at Webb, but knew he had a better chance at getting into college via football.

Pennington was recruited by only two colleges, Middle Tennessee State University and the University of Tennessee at Chattanooga. In 1995, he went to a training camp at Marshall University, his parents' alma mater, where he was noticed by head football coach Jim Donnan and offered a scholarship.

Originally the Thundering Herd's fourth-string quarterback in 1995 and slated to be redshirted, Pennington led Marshall to the 1995 NCAA Division I-AA Football Championship Game, which Marshall lost to Montana, 22–20. The following year, Pennington was redshirted in favor of Eric Kresser, a transfer from the Florida Gators, who guided the Herd's return to the I-AA Championship game (a victory) in 1996. Pennington returned to play in 1997 as Marshall moved from Division I-AA to Division I-A, and led the nation in passing touchdowns with 39. He led Marshall to the school's first bowl game victory in a 48–29 rout of Louisville in the 1998 Motor City Bowl. Pennington was named the game's MVP. In his senior year (1999), Pennington led the NCAA in completion percentage (67.9%) and again in passing touchdowns (37). Marshall went undefeated at 13–0 as Pennington led the team to its third consecutive Mid-American Conference championship. Pennington and Marshall returned to Pontiac, Michigan for the 1999 Motor City Bowl, where they won, 21–3, over BYU, capping Pennington's undefeated senior season.

Pennington set school records in several passing categories. He finished fifth in 1999 Heisman Trophy voting. Randy Moss was Pennington's top receiver at Marshall. Pennington finished his career at Marshall with 1,026 of 1,619 completions for 13,423 yards and 115 touchdowns with only 45 interceptions.

In addition to his success on the football field, Pennington excelled academically, graduating with a degree in journalism, a 3.83 grade point average and becoming a finalist for the Rhodes Scholarship. He wrote frequently for Marshall's newspaper The Parthenon and was a broadcaster for the school's radio station WMUL, although he used a pseudonym on air so as not to be distracting.

Pennington was selected by the New York Jets in the first round of the 2000 NFL draft, 18th overall and the first quarterback taken.