I have argued before that tackling teacher shortages starts with retaining the people who enter the profession. Yet why do so many newly qualified teachers leave? A new study from Flanders, published in Teaching and Teacher Education, offers some answers about teacher retention. Its central message is surprisingly simple: stability matters, and perhaps more than we often acknowledge.

Jacob Van Belle and Mike Smet examined how long newly qualified teachers in Flanders remain in the profession. Rather than relying on surveys about intentions to leave, they used administrative data covering every graduate from Flemish teacher education programmes between 2008 and 2021. In total, more than 55,000 teachers were followed for up to ten years.

Methodologically, the researchers did something important. They looked not only at who leaves teaching, but also at when they leave. That may sound like a technical detail, but it makes a substantial difference. Teacher attrition is not a single event. The timing matters.

The results are both predictable and striking. The highest rates of attrition occur during the first two years of a teaching career. After one year, approximately 85% of teachers are still working in education. After ten years, that figure drops to roughly 69%.

Another notable finding concerns so-called second-career teachers, people who enter teaching after working in another profession. They are significantly more likely to leave teaching than those who chose education as their first career. That difference remains even after controlling for other factors.

There is, however, a more encouraging nuance. The retention of second-career teachers appears to have improved in recent years. Policymakers looking for reasons for cautious optimism may find something to like in that trend.

But what actually predicts whether teachers stay?

The strongest predictors are not mysterious psychological variables or abstract notions of motivation. Instead, they are remarkably concrete:

• full-time employment,
• longer contracts,
• fewer gaps between appointments,
• and greater access to permanent positions.

In other words: job stability.

That sounds almost banal. Of course, people are more likely to stay in a profession when they have a stable income and some degree of certainty about the future. But that is precisely why the finding matters. Discussions about teacher attrition often focus on passion, autonomy, well-being, resilience, or even a sense of calling. This study suggests that employment conditions and career stability may be even more fundamental.

It is also difficult not to see a connection with ongoing debates about tenure and permanent contracts. The study does not prove that permanent appointments are the solution to teacher shortages. But it does add another piece of evidence to a discussion that is unlikely to disappear anytime soon.

The findings themselves are not particularly surprising. Teachers who spend years navigating temporary contracts, fragmented timetables, multiple schools, and uncertainty about the following school year face more than administrative inconvenience. Such instability makes it harder to develop professionally, build relationships with colleagues, and feel genuinely connected to a school community.

Interestingly, the researchers also uncovered several less intuitive findings. Working across multiple schools early in a teaching career was not necessarily associated with higher attrition. Paid overtime was even linked to slightly higher retention rates. One possible explanation is that motivated teachers are willing to take on more complex assignments, provided those assignments also offer sufficient stability and security.

The study also confirms a pattern observed elsewhere. Secondary school teachers leave the profession more frequently than teachers in pre-primary or primary education. This difference is especially persistent among second-career teachers. One plausible explanation is that their subject expertise often remains highly valuable outside education, giving them more alternative career opportunities.

Equally interesting is what the study does not find. School characteristics appear to be only weakly associated with attrition. Even the socio-economic composition of the student population shows little clear relationship with whether teachers stay or leave. This does not mean context is irrelevant. But it does suggest that public debates sometimes simplify the issue too quickly by focusing on “difficult schools”. That is a mistake I have made myself in the past.

Methodologically, I think this is a strong study. It combines large-scale longitudinal population data with precise measures of teacher attrition and sophisticated statistical modelling. Importantly, it also examines how the effects of different factors change over time rather than treating a teaching career as a static phenomenon.

Naturally, limitations remain. Administrative data reveal little about motivation, collegial support, school culture, leadership, or perceived workload. And as with most observational research, establishing causal relationships remains difficult. Yet that limitation makes one aspect of the findings even more interesting. Despite the absence of many psychological and organisational variables, structural factors emerge very clearly.

Perhaps that is the most important takeaway. Discussions about teacher shortages often focus on recruitment. This study suggests we may need to pay at least as much attention to what happens after teachers enter the profession. Retention is not only about motivation or resilience. It is also about whether we offer people a career that feels stable enough to build a life around.