If only governors could borrow Albus Dumbledore's sorting hat, the problems of choosing a headteacher would be made considerably easier. No need to spend hours poring over application forms and devising cunning in-tray exercises to deduce whether one candidate or another best fit their school's needs and ethos. Just pull out the Hogwarts hat to discover the perfect fit.
But the National College for School Leadership has devised a programme that could help take some of the guesswork out of recruitment - urban leader assessment centres.
For pound;1,000, schools can see how their candidates measure up after a day of exercises that simulate the working life of a head. The potential heads are assessed against the college's nine criteria for a successful school leader (see box), including interpreting data, preparing improvement plans and management, in exercises that involve role play and simulation. A rigorous profile prepared by experienced assessors can help governors sort the sheep from the goats.
"The problem for many governors is that as they don't recruit headteachers very often, if at all, they never become experts. So how do they identify the best candidate? Assessment centres have been used very successfully for a long time in many other walks of life," says Alastair McDonald, who has been head of Morpeth high, in Bethnal Green, east London, for 13 years, and is a centre graduate. He is also a part-time secondee to the NCSL, working on the urban leadership programme.
Tim Baker was an early "guinea pig" on the pilot for London schools. He was sent to the Hackney centre by the governors of Charlton Manor primary, in Greenwich, after making their headteacher shortlist. "I had no idea what to expect, but it was a great experience. It was challenging, but it also made me think much more clearly about my plans for the school. That definitely helped me at the job interview the next day," says Mr Baker, who eventually became Charlton Manor's head last September, after two years as deputy head.
Jim Draper, the school's chair of governors, says the recruitment panel made the right decision to send their two shortlisted candidates to the centre. "It provided us with valuable independent confirmation of what we thought was a very strong internal candidate. We were slightly nervous about it all, but the profiles we received back were extremely detailed and very useful. pound;1,000 can seem a large sum of money for a primary school like ours, but if you get the wrong head it can be far more expensive."
Mr Draper also believes the profile of the successful candidate can also be used as a starting point for the head's performance management. "We were able to start with a better view of Tim's strengths and weaknesses. We didn't have to wait a term or two to see them develop," he says.
The scheme also offers coaching for all candidates who attend the centres, whether or not they become heads. This is a benefit discovered by serving heads who have used the centre to gain chartered urban leader status.
Rachel Macfarlane, head of Walthamstow school for girls, in north-east London, was so impressed that she agreed to become an assessor after a day at the Hackney centre.
"It was a very useful experience. It offered a 360-degree look at how I operate in a way that other programmes I have been on didn't. I had never been observed giving feedback to a teacher after monitoring a lesson, for instance. That was very interesting and I am now looking with my deputies at how we can use it in school," she says.
Ms Macfarlane is now reviewing the school's self-evaluation policy with a view to offering improved professional development, and encouraging her deputies to attend the centre.
Alastair McDonald has made changes at his school since attending the course and being forced to think about the way he carried out his role. "When I went through the course I could really identify my job in the exercises, which isn't often the case. It stimulated me to think more clearly about what I do and why," he says.
Now working with the college and the consultants Hay Group to develop the assessment centres, Mr McDonald is keen to allow others to join the 70 who took part in the pilot scheme. "This is an extremely robust system and we have to ensure that quality control is maintained as we scale it up across the country. The pilot scheme was for urban schools - now we are working on how to make the exercises contextually relevant for other sorts of schools so that candidates in Norfolk are not presented with situations more relevant to Lambeth," he says.
Nine criteria for leaders
* Courage and conviction
* Enduring resilience
* Community engagement
* Open and connected leadership
* Develop, coach and listen to staff, so that they can succeed in the initiatives you delegate to them
* Focused vision and simplicity
* Leading learning innovation
* Filtering, judging and acting
* Interpreting data accurately.