Pity the poor CD-Rom developer. Only about 10 per cent of titles make money, largely because it is so difficult for publishers to get their works seen.

"It's impossible for us to show everything, even in our Oxford Street store," says Gerry Berkley, responsible for CD-Rom buying at the high street retailers HMV.

The number of CD-Rom titles grew by 50 per cent last year, and there are some 13,000 on the market worldwide. Most are in English and are looking for shelf-space in the UK. "You have to put at least as much into the marketing as into developing the product if you want it to succeed," says Mark Edwards, managing director of CRT Multimedia, which recently had a Top 10 hit in the US with its EasyTutor Windows 95 CD-Rom.

"You really need a presence," says Gerry Berkley. "New publishers must show us a well thought-out programme to get on our shelves."

Microsoft and Dorling Kindersley, with plenty of product and co-ordinated packaging, have established their brands. Dorling Kindersley sells a lot of its CD-Roms through its Family Library, where representatives visit people at home and have the equivalent of Tupperware parties. Many other non-traditional distribution services are developing. John Gray, president of Philips Media Systems, is in charge of CD-i business in the US. He has 300 titles but, he says, "even the most enthusiastic CD-i retailer will not stock more than about the top 20 titles". So he has taken to mail order - the Gold Club sends discs to 100,000 customers direct. He is about to open it up to independent producers.

With a 30-day money-back guarantee, he sees this as a way of pushing up quality. "This industry needs to grow up fast. We are in an immature market with an antiquated distribution system and some poor-quality product. The good news is things are getting better because consumers are starting to demand higher quality."