The news that recruitment of headteachers is still proving difficult is not surprising. There is undoubtedly a supply problem, fuelled by more heads reaching retirement age and the reluctance of those following to take on a job that has expanded to the extent that it no longer seems possible for one person to fulfil it.

We have two options: to fill the posts swiftly, whatever the cost; or to re-evaluate whether the lone head is the best leadership model for 21st- century schools.

Many schools have already recognised the importance of distributing leadership. They have moved away from the hierarchical model towards more extended leadership, with teams taking collective responsibility for running various aspects of the school. The idea is that leadership is collaborative, which does not mean everyone leads, but that leadership capacity resides in the many rather than resting on a few.

We need not eradicate the post of head altogether, but a mixed economy of leadership models is necessary to ensure our schools are properly led. The alternative is to hope for a thousand heads to ride over the hill and rescue schools. While we are waiting, it might be wise for us to think about mobilising the leadership capacity that already exists in our schools.

Alma Harris Professor of educational leadership at the the Institute of Education, London.