I worked in the charitable independent sector for 40 years, 24 of them as a head. I shall be eternally grateful to that sector for allowing me to lead a hugely rewarding career. I would die in a ditch to defend my sector and the schools in it. Yet I fear for its future. I am concerned that charitable independent schools in the UK are marching steadily, resolutely and confidently over the edge of a steep and life-threatening cliff.

Why? Independent schools are privileged: in the pupils they have, the parents who frequent them, the staff they attract, the money they can charge and the resources they possess. Privilege is fine, as long as it gives back to wider society something in proportion. With their freedom from crippling government bureaucracy, independent schools should innovate and be the cutting edge that acts as a beacon for education in general.

The history is there. Thomas Arnold and Edward Thring were extraordinary pioneers in their day. Frederick William Sanderson at Oundle School invented workshops before many in education could spell them, never mind include them. Schools such as Bedales and Frensham Heights broke the mould when they were formed, not least in pioneering co-education. Girls’ schools played a huge role in the emancipation of women.

And now? I am at a loss to think of a single scheme in the independent sector that is going to be remembered 100 years from now or has the potential to change the face of UK education for the better.

The sector does not help itself by refusing to speak with one voice. Eight organisations speak for the 7 per cent of UK pupils in independent education. Even one of the best, the Headmasters’ and Headmistresses’ Conference (HMC), shoots itself in the foot by appointing its chairman annually. Just as the person learns what the acronyms stand for and who really pulls the strings, they are put out to grass. The lack of continuity infuriates and confuses the government, and with organisations such as the Girls’ Day School Trust also vying for headlines and pursuing a private agenda, the structure by which independent education speaks to the wider world is a dog’s dinner. Divide and rule? It’s more a question of divide and be ruled.

The steady rise of fees over and above inflation is indicative of a sector that tells parents what they need to hear, instead of listening to what they want. Independent schools are in danger of pricing themselves out of the market. They are also in danger of becoming the sole preserve of the UK’s most wealthy families.

Red light flashing on the dashboard? My father was a Sheffield GP who was able to send three sons to boarding school. Try that now. I have met a growing number of independently-educated young parents, our schools’ most obvious market, who have moved to the catchment area of a good state school, having baulked at the prospect of paying fees.

I feel in my bones that the way the numbers are stacking up, our sector is perilously close to tragedy. I do not know what the percentage is of the population who could afford to send their children to one of our schools - 10 per cent? 15 per cent? I cannot say exactly, but I do know that we are creeping ever closer to the lower figure, and it doesn’t leave enough people on the ground to stand and fight for us when the going gets rough.

Times are changing

Life has moved on since the 1920s; the way our schools are governed has not. I have been privileged to serve with two outstanding chairmen of governors, but that our system can work so brilliantly well covers up how often it can go wrong. I suspect that few barons of industry who sit on a governing board would choose to have as the final authority for a new company they were setting up 15 or so people appointed without job description or advertisement. Few in business would select people whose only common denominator was inexperience in running a company of that type, who were subject to no appraisal or review of their performance and who could meet as infrequently as three times a year.

Realistically, in most of our schools, there is no way the executive branch can restrain or complain about an all-powerful chairman. In what other walk of life do we have a situation where if a head has a complaint about the chairman, nine times out of 10 the only person they can complain to is the chairman?

My fear is that independent schools are like a Doctor Who who has forgotten how to regenerate. Before the 1960s, academic achievement hardly ranked in many public schools. When large numbers of grammar school boys started to gain university places, public schools embarked on one of the quickest internal revolutions and adaptations to a changing market in history. Almost overnight, in reaction to a clear threat, they became the bastions of academic excellence they now are. This has been their secret and it has led to years of success.

So where is the next regeneration? We live in a world in which increasingly politics is dominated by a fourth party - not UKIP, but the Party of Envy. Two of the three main parties hate independent schools to the core of their being, and the third is run by so many public schoolboys that to extend even the merest hand of friendship to independent schools would knock them into a trap the media are baying for them to fall into. The world is changing around us. Adapt or die? I fear so, but I also fear that if our species of school becomes extinct we have only ourselves to blame.

Martin Stephen is former high master of St Paul’s School and was chairman of HMC in 2004.