Adjunct Prof Dillon is Director of the National Acoustic Laboratories in Sydney. He has performed research into many aspects of hearing aids. At various times he has also been responsible for the design of hearing aids and for the co-ordination of clinical service provision.

Most recently, his research has concerned signal processing schemes for hearing aids, prescription of hearing aids, evaluating the effectiveness of rehabilitation, electrophysiological assessment, auditory processing disorders, and methods for preventing hearing loss. Amongst his over 150 publications is a comprehensive text on hearing aids that is used widely throughout the world.