Frost was a coach on the Australian national teams for the 1995, 1997 and 1999 Pan Pacific Swimming Championships; the 1998 World Aquatics Championships and the 1998 Commonwealth Games teams and the 2000 Sydney Olympic Games team. He has been a director at the Australian Swim Coaches Association since 1989 and at the Doug Frost Swim School since 1978. After Thorpe controversially changed coaches, Frost left the Padstow club to start afresh in Southport, Queensland. In May 2005, he was appointed the head coach of the swimming program at the Australian Institute of Sport.