[1][2] Born in Newcastle, New South Wales, Morris-Nunn studied architecture at the University of Sydney.

The importation of "William Morris" and the dropping of his father's given name, Arthur must have occurred after he reached his twenties.

He has consulted to the National Trust of Australia (Tasmania) and the Tasmanian Heritage Commission on the classification of buildings from both the 19th and 20th centuries.

In 2006 he completed a Master of Architecture (by invitation) from the Royal Melbourne Institute of Technology (RMIT).

[7] His firm MN+ A, which is now Circa Morris Nunn Chua, has won the greatest number of design awards ever received by any individual or architectural practice in Tasmania, past or present.