Walker played in the winning 1989-90 FA Youth Cup Tottenham team overcoming Middlesbrough. After starting out with the team in the 80's as a trainee and having two loan spells, for Ipswich Town and Oxford United. During the early 90's he succeeded Erik Thorstvedt as the number 1 at Spurs, starting to get his chance in the team during the first season of the Premiership during the 92/93 season. Walker made a total of 312 appearances for Tottenham Hotspur and won the 1999 Football League Cup Final after beating Leicester City 1–0 at the old Wembley Stadium. However, he made several high profile gaffs during his Tottenham career and Walker handed in a transfer request in September 2000 after losing his place in the first team to Neil Sullivan. He played his final game for Spurs against West Ham United on 31 January 2001.