Draw a mental picture of a famous leader, any leader, and the chances are you will see him - nearly always him - alone. Hitler is on a podium high above the Nuremburg crowds. Mahatma Gandhi sits cross-legged on his floor.
Churchill is words coming over a radio. Thatcher stands at the despatch box on the day of her deposing.
The loneliness of leadership is pretty much axiomatic. The buck stops there. But a moment's thought fills in the picture: the crowds saluted Hitler; Gandhi led millions in their fight for independence; Churchill voiced the feelings of his countrymen; the Tories behind Thatcher that day had feted her through three general elections.
So our view of leadership morphs from one of splendid isolation to something a little more co-operative. Leaders are people doing something that lots of people want, or at least think they want. And there's an ambiguity creeping in already.
Leadership is a slippery thing to define. You can go for military definitions, of course. According to the Defence Leadership Centre, set up by the MoD to deliver research and training: "Military leadership is the projection of personality and character to get subordinates to do what is required of them and to engender within them the confidence that breeds initiative and the acceptance of risk and responsibility."
Or you can go for the political with Dwight Eisenhower: "Leadership is the art of getting someone else to do something you want done because he wants to do it."
And then there's the philosophical, from Mahatma Gandhi: "My life is my message."
With leadership very much an issue of the day in the public services generally and in education in particular, it's a good time to ask some basic questions: What qualities should a leader have? How does a leader differ from a manager? And can leadership be taught?
Kate Griffin, president of the Secondary Heads Association and headteacher at Greenford high school, a large comprehensive in west London, says:
"Leadership needs honesty. You are establishing the principles by which an organisation operates. You must make sure the people following a particular programme trust you and know you believe in it. Your behaviour should illustrate the underlying principles.
"The ability to communicate those principles is vital. Most successful leaders tell stories, putting a situation into language everyone can understand and making sure the story includes everyone. Then people feel there's a place for them in the project.
"Inspiration usually crops up in discussion of leadership and I think there's a fine balance to be held here, because charismatic leaders are not necessarily a good thing. To me, inspirational leaders can be dominating, which isn't helpful because it can cause too much reliance. Having said that, if your values are clear in everything you say and do, that's a very positive form of inspiration."
Honesty and communication skills are thankfully not such rare qualities, so you might expect there to be something else which sets leaders apart. But Alex Haslam, professor of social psychology at Exeter University, challenges the whole notion of being set apart by super qualities.
"Successful leaders of organisations are rarely, if ever, mavericks set apart from those they lead by virtue of superior intellect, personality or heroism. This is for the simple reason that successful organisations are collective achievements that have little use for personal indulgence," says Professor Haslam.
"Accomplished leaders have much in common with effective stand-up comedians. Success in both spheres depends upon an ability to adapt to the tastes and prejudices of a particular audience in order to establish a mutually sustaining rapport that allows for the collaborative exploration of new territory."
Storytellers, comedians, performers, but not charismatic pied pipers.
Leadership emerges as something mutual, a group thing. It was the 19th-century French politician and champion of universal suffrage, Alexandre Ledru-Rollin, who said: "There go my people. I must find out where they are going so I can lead them." But who decides where they are going in the first place? That too may be a group thing, according to Haslam, who believes that leaders are created to some extent by the immediate situation rather than by their innate characteristics.
"Our research suggests that effective leaders are those whose individuality is transformed by group membership in such a way that they come to articulate, embody and direct the collective interests that they share with other group members. These attributes cannot be reduced to enduring personality characteristics.
"Leadership, then, is a process of mutual influence that centres on a partnership in an identity-defining relationship. In this sense, leaders are entrepreneurs of identity who create, co-ordinate and control a shared sense of 'we-ness'. What 'we' means is negotiable, and so too is the contribution that leaders and followers make to any particular group's self-definition. But it is only because they are partners in a relationship of this form that leaders and followers have the capacity to empower and energise each other."
"We-ness" may not be a phrasemaker's dream, but it immediately applies itself to one of our major business leaders, Richard Branson. All the employees of the Virgin empire have the chairman's phone number, and when they have a good idea they can ring him. One of his flight attendants did just that when her wedding plans were driving her to distraction. What she needed, she told Branson, was a one-stop wedding service. Virgin Bride, package wedding company, was born.
This is more than identifying yourself with your company; it's the "mutually sustaining rapport" that Haslam talks about. It's also what happens with the school council at Kate Griffin's Greenford school.
Schools, after all, are full of leadership, whether it's in the head's office, the individual teacher's classroom, or on the sports field.
"It's part of a teacher's duty and responsibility to elicit leadership in youngsters and teach them that any sort of decision-making process comes with responsibility," she says. "School councils are a good source of leadership. We have a thorough system of council elections, and lessons are cancelled for the meetings so everyone knows they are important. The school council is always taken seriously and listened to: they always interview candidates, teachers as well, for school posts.
"If management is about getting jobs done, leadership is about principles and philosophy. Increasingly in schools we are talking about leadership teams, rather than one superhead. In many respects the leadership of any institution is there to ensure that the ethos underpinning the place is held firm and that the leadership team is very clear about what the values are and able to communicate them to others."
The difference between management and leadership is only now being recognised in the public services. Courses in management abound, but the chances of finding an advert for an MA in leadership are slim. It may be coyness; it may be the feeling that leaders are born, not made.
Exeter is one of the few universities that teaches leadership, and calls it just that. Alan Hooper, founder and associate of the centre for leadership studies at Exeter, believes we need to recognise the quality and train for it.
"The problem with leadership is that it does not appear in people's titles, and yet we expect senior managers to display leadership in their everyday work. We talk about chief executives, managing directors and headteachers, but are reluctant to use the word leader in their titles," he says.
"We expect leadership from our managers, but we do not prepare them for this most exacting of roles. Leadership is essentially about dealing with people. It requires an ability to relate emotionally so that individuals become inspired to perform above the norm, continuously. But, first of all, a leader has to be aware of his or her own strengths and weaknesses, and to be comfortable with these. Only then can he or she start to develop the skills to relate to people effectively.
"This self-awareness is the start of a process which enables a leader to develop the kind of behaviour that encourages people to work for him or her willingly, and to produce excellent results. From this basis of shared values it is possible to create the vision, set the direction and develop the alignment that is essential for all successful organisations, be they businesses or schools. All this takes time to develop. It may not be possible to teach leadership - but it can definitely be developed."
Useful books: Intelligent Leadership : Creating a Passion for Change, by Alan Hooper and John Potter (Random House); Psychology in Organisations: The Social Identity Approach, by Alexander S. Haslam (Sage)