Ian Walker was for many years the first choice goalkeeper for Tottenham Hotspur, starting out with them as a trainee and having two loan spells, for Ipswich Town and Oxford United. The highlight of his time at Spurs was winning the League Cup in 1999 after a 1-0 win against Leicester City.

After making 312 appearances for Spurs, Ian left in September 2000 after losing his place in the first team to Neil Sullivan. Ian signed a four-year contract with Leicester City in July 2001 for a fee of £2.5 million. His first season at the club ended in relegation to the First Division but then had an impressive season with Leicester as they regained promotion to the Premier League, earning his first England recall in six years in May 2003. His last appearance for England came in a 6-1 win over Iceland in June 2004.

After four years at Leicester Ian moved to Bolton Wanderers on a one year contract.