Initially an executive officer in the Home Civil Service, Cartwright's political career began when he became a constituency agent for the Labour Party in 1955.

[1] Serving twelve years in that role, he was later employed as political secretary of the Royal Arsenal Co-operative Society (R.A.C.S.)

A close political ally of David Owen, he stayed loyal to Owen's 'continuing' SDP after the Liberal Party and a majority of the SDP merged in January 1988 to become the Liberal Democrats.

After leaving active politics he went on to serve as deputy chairman of the Police Complaints Authority before retiring to Kent.

This article about a Labour Party member of Parliament representing an English constituency is a stub.