It is a brave publisher who launches an encyclopedia simultaneously on CD-Rom and in book form these days. Sales of print editions have plummeted since the advent of multimedia versions. It seems children love the lively presentation of information on CD-Roms and parents like paying less for the silvery disc than for the multi-volume set of books.

Nevertheless, Oxford University Press is about to offer such a choice for its revised, expanded edition of the Oxford Children’s Encyclopedia, at Pounds 150 for the nine-volume set and Pounds 59.99 for the CD-Rom, both due to be published in mid-October. This was first published in book form in 1991 and is aimed at 8 to 13-year-olds. Like almost all multimedia encyclopedias, the CD-Rom version throws in extras - a dictionary, a game, and a multitude of animations and videos that bring information to life in the way that the printed page cannot.

But if you don’t have the luxury of a choice between the CD-Rom and the print version, be reassured by the appearance of many of the CD-Rom’s static features in the books.

Those who favour the printed word claim children enjoy the detective work of hunting down information. “Children are capable of spending an amazingly long time in acquiring knowledge, in soaking up the open page,” says Ben Dupre, the editor who has masterminded the overall revision of this en-cyclopedia. Others would claim that print-trained youngsters are better able to communicate ver-bally than those who have been fed with frames or windows of information strung together in bytes, but lacking a cohesive whole.

But some children, particularly those with learning or behavioural problems, can better absorb information presented to them on a screen which they believe they control. This gives them confidence and a sense of achievement. Crucially, as David Hassell of the National Council for Educational Technology points out, familiarity with interactive CD-Roms provides a training in electronic information retrieval and in the skills of IT communication - essential requirements for children today.

A recent report has estimated there are up to 2.5 million multimedia PCs in British homes - and ownership is forecast to reach 3.5 million by the end of next year. Market penetration is highest among families with children aged between 11 and 15, and recent figures show that more than half of these homes own a multimedia encyclopedia, typically “bundled” with other software when the machine was bought.

But many of these are written for the 12 to 14-year-old user upwards and, with the exception of the relatively small Hutchinsons, all are American in origin. This makes the publication of the revised Oxford Children’s Encyclopedia, specifically for younger children, all the more welcome.

Historically, the predecessor of the Oxford Children’s Encyclopedia was the Oxford Junior Encyclopedia, on which generations of children from the 1950s to the 1980s were brought up. It contained about 4 million words - and many believe it offered enough breadth, depth and readability to have served pupils up to A-level and beyond.

Less ambitious in scope than the Oxford Junior, the Children’s Encyclopedia nevertheless reflects a diverse and multicultural society. Its major article on Caribbean history; its treatment of the major world religions; its coverage of new fields such as genetic engineering, plastic surgery, and biodiversity all earn it full marks as a reference tool for the modern pre-adolescent.

Coming as it does from a publishing house that is experienced in presenting educational material of integrity and imagination, this encyclopedia stands confidently above every other UK or US product currently selling to the junior market.

The only criticism is that many of the articles are too lightweight for national curriculum work. A 12-year-old, for example, who is set a project on a core curriculum subject such as the Vikings or the Aztecs, would find no more than a preliminary 600 words on each in the Oxford Children’s Encyclopedia.

To find out more, he or she would currently need to turn to one of the US multimedia encyclopedias in which coverage is likely to be more extensive and helpful for school work.

The OUP is a charitable foundation and therefore exempt from the 33 per cent corporation tax faced by commercial publishers. And as it has no shareholders, there are no dividends to eat into profit margins.

It may be argued that there has been a strong cultural and commercial need for a publisher with the financial resources of OUP to create a British multimedia encyclopedia for older children and home us.ers.

Instead, it has licensed the text of one of its most popular encyclopedias, the Oxford Illustrated, to a newcomer, Softkey. This American multimedia company is set to adapt the encyclopedia for CD-Rom for sale in the secondary school and home consumer market.

The revised Oxford Children’s Encyclopedia, at 850,000 words of text, lives up to the reputation earned by the first, slimmer edition, of informing and entertaining the primary child.

Whether on CD-Rom or in print form, it is attractive, fun to dip into, and stimulating. Its editors, aware of the constraints imposed upon them, have polished each article so that no superfluous word remains, no mindless videos or sound clips distract the user. This encyclopedia will give nothing but pleasure and an appetite to explore further - even if the trail leads back squarely to the American encyclopedias.

Oxford Children’s Encyclopedia on CD-Rom for Apple and Windows, Pounds 59, inc VAT.

Oxford Children’s Encyclopedia (book), Pounds 125 (from January 1997, Pounds 150).

Multimedia and the Consumer is available from Book Marketing Ltd at 7A Bedford Square, London WC1B 3RA. Tel 0171 580 7282; fax 0171 580 7236