A combative and strong-running right back, Mills' World Cup hopes were strengthened by the unfortunate injury to Gary Neville.
His unfortunate habit of picking up yellow cards has not gone down too well in the England camp.
However, he clearly showed enough in the friendlies against Italy and Paraguay to convince Sven-Goran Eriksson that he is worth the risk.
And after accepting the blame for Sweden's goal in England's opening World Cup match, Mills returned to form with an excellent performance against Argentina.
Can play as centre back if required and has improved immeasurably since David O'Leary took over at Leeds.
Started as a trainee at Norwich before moving to Charlton. Left the Addicks for Leeds in 1999 for £4m.