He played as a midfielder from 1982 until 2001 notably in the Premier League for Blackburn Rovers where he was amongst the title winning side of 1995.
He also played in England's top flight for West Ham United and Southampton, as well as playing in the Football League for Wolverhampton Wanderers. Slater also played in Europe for Anderlecht and RC Lens as well as playing in has native land for St George Saints, Sydney United and Northern Spirit FC.