A "strong running and skilful passing"[4] Australian international and New South Wales State of Origin representative second-row forward, Cartwright played his club football with the Penrith Panthers, winning the 1991 premiership with them.

In 1988, under the guidance of Ron Willey, Penrith developed a heavyweight, aggressive forward pack of which Cartwright and second row partner Mark Geyer were the cornerstones.

Unfortunately, a late injury to Ian Roberts forced him to play in the front row,[4] to which Cartwright was ill-suited, and he was dropped after one match.

Cartwright played in all three games for New South Wales (scoring a rare try in the third) and took over the Penrith captaincy when Greg Alexander was injured.

[7] After four years without making the finals, on 5 August 2014 he announced that he would stand down as head coach of the Gold Coast, with immediate effect.

He would coach the club one last time against the Sydney Roosters in Round 22 before Neil Henry taking over on an interim basis.

[8] In February 2015, Cartwright joined the North Queensland Cowboys as an assistant to head coach Paul Green[citation needed].

On 4 October 2015, Cartwright was a member of North Queensland's coaching staff in the side's 17-16 Grand Final victory over the Brisbane Broncos.

In the weeks following the Grand Final win, Cartwright quit the North Queensland club and returned to Sydney as an assistant coach of the Manly-Warringah Sea Eagles.