School improvement is a complex undertaking for any school but for those in the most disadvantaged areas, it presents extra challenges.

In particular, for schools facing multiple disadvantages, improvement can be extremely fragile and changes are not always permanent. All schools go through cycles of change and development but for those in “challenging circumstances”, these cycles are less predictable as they are at the mercy of a range of external factors that can create a crisis at any moment.

Add to that the problem of teacher supply and, on a daily basis, these schools are operating with an imperfect set of arrangements. Add again a constantly-shifting pupil population and the word “challenge” inadequately encapsulates the difficulties they face.

In terms of performance, schools with multiple disadvantages almost always fall short of national averages. There are exceptional schools that buck this trend but they remain a small minority despite sustained efforts by their teachers.

So what is to be done? We could accept that there is little these schools can do, given their conditions. This deterministic, pessimistic position is certainly favoured by some despite several decades of research that points towards the possibility of improving schools, irrespective of context.

This is not to disregard the influence of poverty or disadvantage on a school’s ability to raise achievement. A more finely grained and context-specific approach is needed - one that takes account of external conditions instead of conveniently airbrushing them out.

We undoubtedly need to know much more about schools facing challenging circumstances and how such schools improve or sustain improvement over time. The empirical base is still thin.

However, schools in these circumstances cannot wait for educational researchers and policy-makers to catch up or for inequities in the system to be eradicated before new practices are adopted. The daily task they face is too immediate, too pressing and too relentless. As this pattern of educational inequality looks set to remain, schools facing challenging circumstances must look for strategies and approaches that will help their school and their students. The solutions to their problems cannot be mandated or dictated.

The communities in which these schools operate are least likely to respond to external pressure or intervention and too many have been failed by the very system they are asked to support and endorse.

The powerful grip that current socio-economic conditions have on schools can no longer be ignored, nor the relationship between disadvantage and under-performance underplayed.

However, while we need to be realistic about the potential to improve schools in areas of disadvantage, we must also find ways of supporting them in their efforts. Research suggests that increasing external scrutiny, intervention and pressure on these schools is least likely to bring about long-term improvement. Quick performance gains are easy to secure, but are unlikely to last over time.

An alternative approach takes into account the differences between schools - particularly between those with common labels and sets of socio-economic characteristics. It suggests that improvement approaches should meet the needs of individual schools, or groups of schools, in their context with their pupils. This implies a much more differentiated pattern of improvement provision for schools, focusing upon real needs rather than perceived needs.

Undoubtedly, this will be unpopular with those who seek quick results in ever shorter time. But, if we are serious about helping schools in challenging circumstances, then we have to accept the need for strategies that are finely tuned to individual schools and individual school contexts.

Professor Alma Harris is director of the leadership, policy and development unit at Warwick University institute of education