Campbell began his career with Tottenham Hotspur in December 1992. He spent nine years at Spurs, scoring 10 goals in 255 appearances, and captaining the team to victory in the 1999 Football League Cup Final against Leicester City. In his five years and 195 appearances at Arsenal, he won two Premier League winners medals and two FA Cup winners medals, encompassing the 2001–02 league and FA Cup double, and being part of the team that became known as The Invincibles for their undefeated 2003–04 Premier League campaign. He scored Arsenal's only goal in their 2–1 defeat to Barcelona in the 2006 UEFA Champions League Final.
Having already won caps for the England under-21s and England B team, Campbell gained his first of 73 full caps for England aged 21. In May 1998, Campbell became what was then England's second-youngest captain, after Bobby Moore, aged 23 years 248 days. In 2006, he became the only player to have represented England in six consecutive major tournaments, playing in the 1996, 2000 and 2004 UEFA European Championships; and the 1998, 2002 and 2006 FIFA World Cups. He was named in the Teams of the Tournament for the 2002 World Cup and at Euro 2004. Other honours in the game include being in the PFA Team of the Year three times, in 1999, 2003 and 2004.