Selection shouldn't focus on older people any more than on groups like ethnic minorities or gays.

One of the most frustrating aspects of HR must surely be keeping the rest of management on the straight and narrow, particularly with regard to employment law. So there must have been a few sharp intakes of breath when Mark Thompson, the BBC's director general, made it known a little while back that he was seeking specifically someone over the age of 50 for a newsreading job.

Here he was responding to criticism that television stations had been too willing to dispense with their older presenters. First there was controversy over the 'retiring' of news stalwart Moira Stewart, 60, and then yet more headlines over the replacement of 66-year-old Strictly Come Dancing judge Arlene Phillips with the 30-year-old former contestant Alesha Dixon.

So Thompson could have been forgiven for feeling he was lining up with the righteous the day it was revealed he had asked talent agents to look around for someone in their fifties. After all, it happens all the time in the discreet conversations that clients have with their head-hunters. It goes something like this: 'Hello, is that Body Snatchers'r'Us? We need to strengthen our board, add a bit of diversity to keep the corporate governance and PC brigade happy. Too many pale, stale, males apparently. How about a clever young woman, possibly with an ethnic minority background? Yes, Scotland will do fine.'

These are the behind-the-scenes realities of recruitment at some levels. There is the law and there are the conversations that clients have with their intermediaries. Intermediaries should know the law and advise their clients accordingly. But employment lawyers were queuing up to criticise Thompson, reminding the BBC that targeting older people for jobs was this time discriminating against younger people, a flagrant example of age discrimination.

Thompson is reported to have said the removal of Phillips was not motivated by ageism and I go along with that. A lot of factors are involved when older employees lose jobs they have been doing for some time. New brooms, for example, are often eager to make changes simply because change is regarded by many as a key constituent of management. An incoming manager, therefore, can rarely resist the temptation to undertake personnel changes since they are visible - like shifting the furniture.

But a swift change of personnel in order to shake up an organisation is rarely a good idea. The sensible manager will take some time to evaluate people in their roles while giving encouragement and help to members of the team who may have been demotivated under the previous regime. The emphasis must be on ensuring the best people are doing the work where their talents are needed most. In spite of the criticism levelled at the BBC, it must be recognised that the broadcaster has maintained high standards among newsreaders and presenters.

Recruiting older people is going to become a feature of employment in the next few years as demographic trends reduce the proportion of experienced younger managers and increase the older demographic among companies' customer bases. But such recruitment cannot be pursued in the spirit of tokenism any more than selection might focus on a section of society such as ethnic minorities, gay people or women. Selection has to consider only the talents of the individual.

Whether those responsible for recruitment are capable of such impartiality is doubtful. Fiona Bruce, the BBC television newsreader, was philosophical when asked earlier this year if, unlike their male counterparts, female newsreaders are judged by their looks. "Of course," she said. "Though no one has ever said or intimated to me that I am a bit of window dressing. It would take a pretty bold and, I suggest, foolhardy person to say that to my face." As Bruce suggests, it is the things left unsaid that remain a cause for concern.

- Richard Donkin is author of 'Blood, Sweat and Tears' and 'The Evolution of Work'; richard.donkin@haymarket.com