The days of the charismatic, autocratic head are over,” declares Frank Clare, the centre manager for the National Professional Qualification for Headship prospective school leaders’ programme in the South-east.

Mr Clare, a former secondary head, believes that the raft of training measures available to school leaders today spells the end of staffroom bullying. And yet, and yet.

Teachers remain the largest professional group contacting the Bully Online website - often complaining about being bullied by colleagues in managerial positions. The degree to which unions are concerned by the phenomenon was illustrated earlier this year with the publication of legal advice on bullying by the Association of College and Secondary Leaders (ACSL, formerly the Secondary Heads Association). But why is the subject so often in the headlines now?

Martin Ward, the ACSL’s deputy general secretary, believes that allegations of bullying often reflect the dislocation between the view many teachers - particularly older ones - have of their job, and what he calls the “outdated managerialism” imposed by government.

“The teaching profession is in the process of change,” he says. “Many older teachers joined when it was seen as a profession like medicine, or architecture, where the professional was traditionally not subject to supervision. Quite a lot of teachers still resent the notion that they can be criticised for what they do in the classroom.”

At the same time, however, the current emphasis on league tables and performance management increases the pressure on heads. If they cannot handle that pressure, and take it out on their staff, a potentially explosive mix is created.

That is where the National Professional Qualification for Headship course for prospective school leaders, and the Leadership Programme for Serving Headteachers come in, says Mr Clare. He believes that they do teach leaders how to manage effectively, and, if necessary, show them that they need to change their attitudes. For new headteachers the NPQH qualification is mandatory, but the LPSH, for established leaders, is not. So what about those heads, already in situ, who can expertly “talk the talk”, but refuse to “walk the walk”?

Catherine, 50, and an experienced assistant head, thought she’d found the ideal job as deputy in a small London primary school in 2001. She was immediately impressed by the head, who spoke about management skills and leading the team, and the school’s excellent results. As soon as Catherine started work at the school it became clear, however, that this was not a happy ship. “The staff, who were generally young, lived in fear of this woman,” says Catherine. “She was a control freak, who found it impossible to delegate, then blamed her staff for her own mistakes, consistently belittling her teachers. She was constantly flying into rages with one or other of us, and no one knew who would be next -it was completely debilitating. Every morning there would be staff crying in the toilets.”

For outsiders, the head - charming and articulate like many classic workplace bullies - had fabricated an image of a successful, well-run school and used her influence with governors and the education authority to keep advisers out.

“She thought she knew everything and used to refuse point blank to attend training courses for heads,” Catherine adds.

Staff who tried to confront the head about her behaviour - the recommended method for dealing with workplace bullies - were shouted down. Those who left -and four teachers were desperate enough to do so with no jobs to go to - were given damning references.

Finally Catherine approached her union, the National Union of Teachers, for advice, and the staff together approached the LEA with evidence against the head, who was forced to take early retirement.

This was an extreme case. On top of everything, the head clearly had “a terrible life-work balance”, concludes Catherine. But it illustrates starkly how easy it is for a school leader who cannot manage effectively - either professionally or in their personal life - to bully. Catherine, who is now acting head, sees this herself. “Headteachers are very powerful.

Teaching is such a personal skill, where teachers need to feel enabled and empowered to give of their best, that that power becomes a very dangerous thing in the hands of a bully.”

As Catherine’s case illustrates, bullying is so much a matter of personality and circumstance that training is unlikely to stamp out the problem completely. Mr Ward suggests that what is needed is a clear understanding at every school and at every level, from newly-qualified teacher to head, about what is reasonable behaviour and what is not.

A printed statement outlining management policy would give a potential victim an objective yardstick on which to base any complaint about a school leader, he says.

But Mr Ward also believes that some teachers - particularly those who resent the concept of accountability - are too quick to level accusations of bullying against managers rightly critical of their performance.

Does this make strong management impossible? No, says Richard Bird, the ACSL’s legal consultant.

“When confronted with difficult or incompetent members of staff, use established procedures,” he advises. Do not isolate (incompetent staff) or treat them unfavourably compared to other staff. Do not be rude or abusive in front of other staff, impose unrealistic performance targets or threaten disciplinary action if targets aren’t met,” he says.

Last but not least, he says, strong managers need to be aware that they are role models.

“While you take a strong management style, your deputy may then be ‘a bit fierce’; and your head of faculty be a bully and think that is what you want.”

But remember that fair criticism, however painful, is not bullying. “Judges have acknowledged that there is a distinction between bullying and strong management,” he says. “They accept that employees may be understandably distressed by managerial conduct which is properly and reasonably critical of poor performance.” There should, therefore, be no problem for a dynamic and forceful head laying down the law to her team at a struggling school - as long as the criticism does not humiliate individuals, is fair, constructive and balanced by a recognition of positive points, he says.