Advertising revenue is up by 25 per cent, year on year, according to the Radio Advertising Bureau, the body backed by local commercial stations to market radio to advertisers. Recent audience research shows that commercial radio continues to win listeners from the BBC - it achieved a 45.1 per cent share of radio listening in the first quarter of 1994.
But all too often advertisers opt for 'headline' style ads, or simply lift the soundtrack from a television campaign. This approach fails to take advantage of the unique strengths of the radio medium and can backfire.
'Radio is the (advertising) creative's final frontier. Creatives have got so used to thinking about visual imagery they are more concerned about whether an idea is original than whether it is good,' says Andrew Ingram, RAB's head of brand development.
Advertising agencies have traditionally regarded radio as a low priority, or as a 'top-up' to television campaigns. This has led not only to poor quality but also inappropriate work. Many new stations are themed, and station managers are keen to ensure the advertising they carry blends with the tone and pace of the rest of their output.
Mr Ingram says: 'Companies ring us and say, 'I would like to use radio, but I don't have confidence in my advertising agency.' ' But, he adds, this is not just the agency's fault. 'Often the client's radio brief is not radiogenic.'
Radio is good at certain things, bad at others, he explains. It is not good at conveying specific, or detailed, product information. But it is good at generating a feeling about a company or product.
Classic FM regularly holds workshops for agencies and advertisers' marketing departments to explain how radio can be used effectively.
About 80 per cent of radio advertising is uninteresting, yet radio is more immediate and personal than television or print, top US radio scriptwriter and producer Dick Orkin told a recent session. 'An astonishing number of radio ads fail to recognise the need to grab the listeners' attention,' Mr Orkin said. To achieve the right tone, the marketing department must clearly define its goals.
This is a view shared by Mandy Wheeler, managing director of Mandy Wheeler Sound Productions, a UK radio production company involved in a series of regional roadshows staged by the RAB to improve awareness among advertisers.
'Many clients still think of radio as an audio Yellow Pages - load it with facts and turn it into an announcement,' she says. 'But radio's strength lies in its emotional contact with the listener.'
For companies whose advertising agencies are less than enthusiastic, independent production specialists such as Ms Wheeler can become involved in production or at script stage. But only greater awareness can improve the situation.
'Clients can take a much more forceful role,' says Nigel Reeve, sales director at Classic FM. 'Agencies have got to give radio the respect it deserves.'
Few doubt that radio works as an advertising medium. The RAB's case studies aim to prove not just that it does, but how. One includes a recent campaign for Younger's Tartan Special that, unusually, used 14 different ads and a creative strategy developed specially for radio. 'It raised the product's image as a good beer,' Mr Ingram says. 'But what it also did was make listeners feel the beer was drunk by people like them and that it was familiar.'
It was an effect that could have cost at least four times as much to achieve on television.
The situation is undoubtedly improving as more national advertisers use radio for the first time, encouraged by growing professionalism within the industry. And the launch of new services, notably the national stations Classic FM and Virgin 1215, has made local advertisers look harder at the creativity of their advertising.
'A growing number of companies are seeing a specific role for radio,' Ms Wheeler says. 'They are no longer treating it as a secondary medium. Once this happens there will be better work, but it has to start with the brief.'