Harris ran the Mary Martin Bookshop in Adelaide with his university friend
Mary Maydwell Martin. They published a monthly newsletter with literary criticism, comment and book reviews. After Mary Martin moved to
India, Harris expanded the book chain across Australia and Hong Kong. The chain pioneered the
remaindered book industry in Australia by offering quality titles at reasonable prices. Harris fought the stranglehold which overseas publishers had on the Australian book market, taking on major publishing houses to ensure accessibly-priced books for Australian readers. The Mary Martin chain was sold to
Macmillan in the late 1970s. Harris founded and co-edited the
Australian Book Review and another literary journal,
Australian Letters, which continued the practice of commissioning artists to illustrate poetry. He was also, together with
Geoffrey Dutton and Brian Stonier, a founder of
Sun Books. Harris published his poetry privately, although it was often included in classic Australian anthologies. He became a long-serving and controversial columnist for
The Australian, with many of his "Browsing" columns later published in book form. It was in this context that he was dubbed "Australia's Cultural Catalyst". He also wrote columns for Adelaide newspapers. Harris campaigned against censorship, and was an early voice in the
Australian republican movement. Although he was not a
Catholic, Harris championed the then little-known nun and teacher,
Mary MacKillop, founder of the
Josephite order, calling her "a saint for all Australians". He became a prominent lay spokesman for her canonisation. Josephite nuns visited Harris in later life when he was ill. His ashes lie in a park between the
Mary MacKillop College and the Josephite Convent in Adelaide. == Recognition and honours ==