After completing in 1971, at the University of Melbourne, an MA in German Literature, with a thesis on the Austrian novelist Adalbert Stifter, Terence O'Neill worked for many years in administration at that University. During that time he also assisted Brenda Niall in the compilation of Martin Boyd (Australian Bibliographies) (1977) and discovered the previously unknown Martin Boyd novel Dearest Idol which had been published in USA in 1929 under the pseudonym Walter Beckett. In 1981 O'Neill was awarded an ARGC grant to travel to England and Italy to interview friends and relatives of Boyd, and these interviews are now held at the National Library. He also visited Boyd's cousin Joan Lindsay at Mulberry Hill on several occasions and was able to establish previously unrecognised connections between their works (Australian Literary Studies, May 1982).
O'Neill then turned his attention to Australian children's books and, with Frances O'Neill, published in 1989 Australian Children's Books to 1980: A Select Bibliography. Since 1994 he has been working on the Bibliography of Australian Literature project at Monash University, where he has been joint compiler of the List of Australian Writers 1788-1992 (1995) and Associate Editor of The Bibliography of Australian Literature (2001-2008) (4 vols). He is at present co-editing a Supplement to The Bibliography of Australian Literature, which it is expected will be published in 2016.