His research interests are: the perception of sound; mechanisms of normal hearing and hearing impairments; relationship of auditory abilities to speech perception; design of signal processing hearing aids for sensorineural hearing loss; methods for fitting hearing aids to the individual; design and specification of high-fidelity sound-reproducing equipment; perception of music and of musical instruments. He is a Fellow of the Royal Society of London, a Fellow of the Academy of Medical Sciences, a Fellow of the Acoustical Society of America, a Fellow of the Association for Psychological Science, a Fellow of the Audio Engineering Society, and an Honorary Fellow of the Belgian Society of Audiology and the British Society of Hearing Aid Audiologists. He is a member of the Experimental Psychology Society (U.K.), the British Society of Audiology, The American Auditory Society, the Audio Engineering Society, and the Association for Research in Otolaryngology. He is President of the Association of Independent Hearing Healthcare Professionals (UK). He has written or edited 19 books and over 700 scientific papers and book chapters. He is an associate editor of the journal Hearing Research. He has been awarded the Littler Prize and the Littler Lecture of the British Society of Audiology, the Silver and Gold medals of the Acoustical Society of America, the first International Award in Hearing from the American Academy of Audiology, the Award of Merit from the Association for Research in Otolaryngology, and the Hugh Knowles Prize for Distinguished Achievement from Northwestern University.