Stephen O’Leary holds the William Gibson Chair of Otolaryngology at The University of Melbourne. He obtained his PhD at The University of Melbourne under the mentorship of Professor Graeme Clark in 1994, and completed surgical training in Ear Nose and Throat - Head and Neck Surgery in 1998. 

Prof O’Leary has undertaken post-doctoral research at Oxford University, UK and the University of Utrecht, The Netherlands. He has worked as both a surgeon and a medical researcher at The University of Melbourne and the Royal Victorian Eye and Ear Hospital, since 1999, and from 2007-2009 serves the Hospital as Chairman of the Senior Medical Staff. In addition, Prof O'Leary holds an honorary clinical appointment at the Royal Children's Hospital, Melbourne, and an honorary research appointment with the Bionic Ear Institute.

Prof O’Leary is recognised internationally for his clinical and research activities in ear disease, hearing and balance, and particularly for contributions to cochlear implantation. The main focus of his translational research is the protection and regeneration of the inner ear regeneration, and in particular, hearing protection during cochlear implant surgery. Prof O’Leary has led the development of a virtual reality simulator to train ear surgeons in collaboration with CSIRO, and this system has recently been licensed for commercial development to an Australian company, Medic Vision. He was elected to the Collegium Otorhinolaryngologicum Amitciae Sacrum in 2006 in recognition of his contributions to Otolaryngology.