It may be little consolation as they struggle with paperwork, find a candidate for that unfillable vacancy or nervously leaf through performance league tables, but headteachers should know they are not alone. Across the globe, school leaders face the most testing of times. They work in an unforgiving spotlight, where assessment and accountability have never been greater. Recruitment is often difficult, financial pressures are tough, and they groan under a seemingly never-ending series of government initiatives and reorganisations.
While they are expected to deliver an unrelenting improvement in basic standards, they are also supposed to keep an eye on the wider picture - to adapt to the new globalised knowledge economy. "Chalk and talk" is out; individualised student plans and pupil-centred learning are in.
"In most countries I work with, the government is setting extraordinarily high expectations," says Professor Brian Caldwell, dean of education at Melbourne university, Australia. "The word Tony Blair uses is transformation."
The stakes are high. In an analysis of global trends in education, the Organisation for Economic Co-operation and Development posits one worst-case scenario, which might be called "meltdown": severe teacher shortages, conflict, falling standards and many parents opting out of school education entirely.
Many heads will recognise the early symptoms as they re-advertise for maths teachers or contemplate middle-class flight from their inner-city schools.
Certainly, few doubt that change is necessary. Professor Caldwell talks of the "morally unassailable" argument that many schools could do better - and if these pressures are prompting a crisis in leadership, then leadership itself is the solution.
"Leadership will be to this decade what standards-based reform was to the 1990s, if what you want is sustainable reform," says Professor Michael Fullan, dean of the Ontario Institute for Studies in Education at Toronto University. "During the 1990s there was a lack of attention to basic leadership in school. While we made some gains in literacy and numeracy, they plateaued because they were based on standards and not on leadership at the school and local education authority level."
But Professor Fullan warns against the appealing chimera of the charismatic leader. "High-profile leaders are a liability for sustainability because the changes they bring are so dependent on them," he says. "The effective leader is not the one grabbing the headlines or even producing the best exam results, but the one ensuring that good leadership runs all the way through the school, and who brings on the next generation."
These leaders - who provide vision for their schools but encourage responsibility and autonomy in their staff and above all demand a new sense of professionalism - are lead learners in what Professor Fullan calls "professional learning communities".
But there are barriers to creating this new kind of leadership, he warns.
The job may be so bureaucratic or time-consuming that it deters candidates.
Others suffer a "loss of moral compass ... you get into a rut. You forget why you wanted to be a leader."
And some simply cannot meet the new challenge. Together, these spell inertia, so outside help is needed.
This can come from other heads or from the wider education system. Michael Fullan and Brian Caldwell are both fans of the UK's National College for School Leadership, not only for the training it offers, but for its research programmes and networks.
On a smaller scale, local education authorities can provide opportunities for collaboration to stimulate fresh solutions. Professor Fullan cites a project in Chicago, where 550 schools have been reorganised into 24 clusters of differing sizes. The weakest 12 schools are in one cluster, the 43 strongest in another. Each cluster is undertaking training to develop strategies to ensure their literacy and numeracy schemes succeed.
In Singapore, school leaders themselves are collaborating toset mutual challenges and help with the formation of a new Academy of Principals out of the three heads' associations.
Singapore's schools are generally regarded as successful, but they too are feeling the heat. Their government has challenged them to adapt to the ever-accelerating changes of the hothouse Asian economy.
Belinda Charles, president of the new academy, suggests there has been too much emphasis on academic results. "If we're not careful, what we teach in school isn't what students need out there. They need the entrepreneurial mindset and the ethics of the workplace." And so do heads, she says - so the academy has set up a business arm to give members a taste of the market.
The academy spreads good practice, disseminates research and aims to become involved in headship training. But one of its first projects has been to second heads to businesses' human resources departments to build their personnel skills.
But what will this new vision of leadership mean for schools around the globe? Professor Caldwell points out that the basic model of schools has not changed in decades and argues that institutions must adapt their structures, develop their own solutions and find their own identities.
The OECD, alongside its "meltdown" scenario, sets out some optimistic possibilities. One sees schools as community hubs, bringing in other professions to provide other services that complement the work of the teachers - from social workers to freelance sports coaches. Another sees teachers networking widely, schools having more staff to allow greater innovation.
Professor Geoff Southworth, director of research at the NCSL in Nottingham, England, says we need to encourage people "to look outside their own context". It is not about finding solutions to your problems that you can transplant in wholesale, but about finding fresh perspectives - "enlightenment", he says.
Traditionally, international links have been used to give pupils contact with different cultures and languages; increasingly they are being used by teachers to share ideas.
So we have schools in Ohio and Finland working together on global citizenship, while Sweden's industry-funded kunskapsskolan or knowledge schools, where students direct their own learning, have inspired one secondary in Bolton, England, to restructure its lower school completely.
The OECD would like to see teaching as a well-rewarded, high-status job - although not necessarily a job for life. It foresees more flexible contracts and teachers perhaps working in several schools at once. They would constantly be reflecting upon and seeking to improve their practice.
Professor Caldwell calls this "the new professionalism". Chief among its strategies is better knowledge management - the need for schools and their leaders to see the big picture, to network and be aware of new research and successful initiatives elsewhere.
"You wouldn't countenance a doctor or lawyer who hadn't read the latest research. We've really moved into the same era in education. The knowledge base is better than it has ever been. Research now tells us how we can help every child in every setting." Just as doctors regularly meet to discuss a problem of the week, go through the latest academic papers or share a particular success, teachers should do the same. Japanese schools already excel at this, Professor Caldwell says.
Alongside knowledge management comes innovation. The Hong Kong government has set up a Quality Education Fund - HK$5bn (pound;385.5 million) invested in the financial markets with the annual interest used to support more than 4,000 innovation projects in its schools.
"It has transformed the culture in less than five years," says Professor Caldwell. Hundreds of projects have helped develop specialisms in Hong Kong's hitherto uniform schools. An accelerated learning programme funds extra staff to help struggling students. And there's Hong Kong Education City, a sophisticated, virtual-learning network.
Professor Caldwell says schools must be prepared to drop not just old ideas or new ones that have failed or run their course, but good ones if it allows even better ones to be brought in - a process he calls "abandonment".
"Many heads are worn down because they keep piling tasks on," he says. But that means governments being prepared to trust the judgment of school leaders.
Which finally begs two questions: first, are our educationists up to the challenge? The encouraging signs are that with an ambitious, techno-literate and global-thinking generation coming through, yes they are. Second, will our seemingly tax-and-spend-phobic governments be prepared to meet the cost? "When you put all the pieces together," Professor Caldwell says, "it requires substantial investment and you dare not leave that until it's too late."
Politicians, it's over to you...
'A strategic view of efforts to lead the transformation of schools' , a paper by Brain Caldwell:
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