Headteachers are extremely important to a school’s success. They can influence teachers’ motivation and students’ performance.

But behind headteachers’ career pathways there is a hidden dynamic that affects the education system in England. Our research at EPI shows that headteachers’ career movements create informal professional networks of schools.

These networks can be powerful ways of sharing expertise, support and best practices, but they are not equally accessible to all schools.

Much like exclusive circles where access depends on connections, these implicit networks can unintentionally lead to segregation in the labour market for headteachers.

Schools isolated outside leadership networks

While some schools benefit from this shared leadership expertise, others are left in the margins. This division has real consequences for pupils, teachers and school communities.

This inequality exists for three main reasons:

• Headteachers clustering within closed networks.
• Selective hiring practices.
• Geographical disparities in leadership access.

Let’s look at each in turn:

1. How career patterns shape school networks

Headteachers’ career patterns create implicit networks between schools, which facilitate the sharing of experience, best practices and support. These networks can be extremely important for headteachers to manage their complex roles effectively.

However, these informal networks are surprisingly closed: headteachers who start their career outside a network are unlikely to access it later. While these networks create a deeply collaborative environment within certain groups of schools, they leaves others isolated. Schools outside of these networks will lack the resources that others have to improve their leadership, as well as teacher and student outcomes.

2. Selective hiring can contribute to gaps

Hiring practices play a significant role in shaping these networks. Schools understandably look for candidates whose values align with theirs. This means they often recruit from familiar professional circles.

They can look, for example, for headteachers from a culture or faith that matches their own. While this ensures a cultural fit, it can reinforce existing inequalities.

Schools already connected to strong leadership networks may end up attracting experienced headteachers, while others, which may be facing challenges, might struggle to do it.

This dynamic means that certain schools disproportionately benefit from the expertise of effective leaders while others are left behind.

A high-performing school, for example, might hire a headteacher who brings experience from a similar institution, further enhancing existing disparities. An underperforming school, on the other hand, may find it harder to attract those highly effective leaders.

3. Geographical disparities in leadership access

Location amplifies these inequalities. Regions like London and the North East are very effective at attracting and training many of England’s most effective headteachers. These areas also have strong professional networks.

In contrast, some regions have a disproportionate number of isolated schools that are disconnected from broader leadership networks. The North West has the largest proportion of isolated primary schools (20 per cent), while isolated secondary schools are concentrated in the West Midlands, East of England, and the South East, each having around 15 per cent of the isolated schools in England.

These schools struggle to recruit the most effective headteachers, making it harder for them to address their challenges or improve performance.

Without access to the experience and insights of well-connected leaders, schools in regions that struggle to develop top leadership risk falling further behind. Other types of support networks, such as peer support programmes or networks created by multi-academy trusts, may be important in these regions where these implicit professional networks are lacking.

Why this matters for students and leaders

Headteachers are enormously important for a school to be successful. EPI’s research shows that highly effective headteachers add the equivalent of two GCSE grades per student across all subjects, and these benefits translate into lifelong gains for students.

However, when leadership talent is unevenly distributed, these gains cannot reach every pupil.

For headteachers, working in isolated schools can also be detrimental. A lack of connection can contribute to feelings of professional isolation, which can lead to poor wellbeing, compounding the pressures of an already demanding role.

Towards a more inclusive labour market

The current system leaves many schools distanced from leadership expertise.

While the unrestricted mobility of headteachers may bring benefits, it could also intensify segregation, with more successful schools attracting the most effective leaders. Policymakers should be aware that, just as exclusive circles can perpetuate privilege, leadership networks may benefit those that are already ahead.

Instead, a more inclusive system should ensure that all schools have access to the leadership talent they need. This might involve encouraging broader collaboration between schools, rethinking hiring practices or creating more opportunities for schools in isolated regions to connect with experienced leaders.

By addressing the hidden barriers in the headteacher labour market, every child can have a better chance of succeeding.

Dr Joana Cardim Dias is a senior researcher at the Education Policy Institute and one of the report authors

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