he flipchart in the corner of the staff meeting room, deep inside a prison in the south-east of England, tells its own story about what our overcrowded jails are having to deal with, day in day out. Under the heading "Challenges", it lists gangs, the destruction of cells, prisoners exploiting each other and complex behaviours.

Committed, hard-working staff talk about the high levels of psychosis, often combined with drug abuse. They provide examples of people actually committing crimes to go back into jail to get some respite from their chaotic, dysfunctional lives.

To tackle the current prisons crisis in England and Wales, planned changes to sentencing will see almost 2,000 people released early from Thursday and over the following month. It is the first tranche of the estimated 5,000 releases that will take place in phases over the coming year.

This will address the immediate crisis, but by the government's own admission it is not a permanent fix. If it wants to ensure that the new approach to early releases does not need to be further accelerated, wider reforms will be needed across the system.

There is a precedent that shows it can be done. When Labour was last in government, in 2010, there were more than 2,000 children behind bars in England and Wales. Today there are fewer than 500. Where there is a will …

• Enver Solomon is chief executive of Nacro, the criminal justice charity