The remarkable number of syndromic genetic hearing loss (about 150), the extreme variety of clinical signs that can be associated with the hearing loss, and the different possible combinations make the diagnosis od syndromic genetic hearing loss sometimes very difficult and motivated the development of an expert system (G-DEAFNEX). A collection centre is proposed: to act as a referral centre, for patients with suspected syndromic genetic hearing loss, that aids the diagnostic procedure; to act as a centre for the collection of data on patients with known syndromic genetic hearing loss; to collaborate with Hearing International in a worldwide epidemiological study on syndromic genetic hearing loss; to refine the G-DEAFNEX expert system.