For lots of us, the prison system isn’t something we are exposed to, or know much about.

If you’re keen on volunteering with us but would like more context or information about how it all works, we’ve summarised some key points and gathered some resources to point you in the right direction. 

For more in-depth perspectives, please see our Podcasts etc page - and don’t hesitate to contact one of the team if you have any questions!


The Government website holds the official guidance on life in prison.

However, this excellent guide from DoingTime goes into greater detail on day-to-day life, including on incentives and privileges system, prison rules, and what to expect:

And the Prison Reform Trust has some great factsheets on specific areas of prison life.



There are also other types of detention facilities, such as Immigration Removal Centres run by the Home Office.

 Scotland and Northern Ireland have their own prison services.

There are 117 prisons in England and Wales, 12 of which are women’s prisons.

The prison system is managed by Her Majesty's Prison and Probation Service (HMPPS), previously the National Offender Management Service (NOMS), overseen by the Ministry of Justice.

The imprisonment rate for England and Wales is the highest in western Europe. While the number of prisoners in England and Wales has fallen recently, evidence suggests that the overall needs of the prison population have increased.

Recent issues affecting prisons include:

Prison systems chart2.png

*in particular, prison officer numbers being reduced from 25,000 in 2010 to 18,000 in 2015

You can read more about prison performance and issues on the Institute for Government’s 2019 publication.


Prisons are either “public” (run by HMPPS) or “private” (run by private companies G4S, Sodexo, and Serco). There are 104 public prisons and 13 private prisons.

All prisons are divided into categories of security. Each offender is assigned to a category, depending on the crime committed, sentence length, risk of escape, and risk of violence. A prisoner’s progression through these categories over time will depend on how they respond to prison rules and regulations and how they have behaved whilst in custody.


are assigned one either Categories A, B, C, and D. Prisons holding offenders classed within Categories A-C are called “closed prisons”, and those holding Category D offenders are called “open prisons”.  


have different categories: Restrictive status (roughly equivalent to Category A), Closed status (roughly equivalent to Categories B and C), and Open status (roughly equivalent to Category D).


are further split into those under 17 and those above. Offenders over 21 are treated as an adult. Each juvenile prison has its own induction and regime rules.

More details on what defines each category can be found in this 2015 House of Commons Briefing Paper.

Local Prisons and Dispersal Prisons are also different from one another.


are prisons where a defendant will be sent initially and assessed, usually local to the area of the court where their trial is held.


 are prisons where a convicted offender will serve their sentence.

Sing Inside works within a range of prisons, but mostly Category A and B prisons.


Most prisons have the same basic departments or facilities. These usually include:

  • A gatehouse and reception

  • A visitors’ centre

  • A canteen

  • An education or workshops area

  • A gym and exercise area

  • An Offender Management Unit (where staff help residents manage their sentences)

  • A healthcare wing

  • A Chaplaincy or multifaith room for emotional and spiritual support

  • A segregation unit for safety or discipline.

Residents are walked between these sites either under specific escort or at “movements” pre-determined by the prison regime.


Prisons are split in various wings, and then again into separate spurs and landings. Each spur has an office which is manned 24/7 by prison staff. Movement between spurs is restricted.

Prisoners are not segregated by reference to their crime. However, the prison will segregate vulnerable prisoners (VPs) from the “mainstream” population as far as possible. A prisoner may be deemed a VP if they are at risk of self-harm, bullying, or attack if kept with the mainstream prison population.

Sing Inside works with people from across the prison population, and we tailor our programmes to meet different needs.

Other specialist wings include Psychologically Informed Planned Environments - “PIPE units” - which aim to provide prisoners with progression support after a period of high-intensity treatment or programmes during their sentence.


The primary purpose of prison staff is “to carry out the instructions of the courts, and to ensure that society is protected”. There are many different types of prison staff, all of whom Sing Inside must communicate with in order to build and maintain a relationship with a prison.

Uniformed staff are either Officer Support, Prison Officers, Supervising Officers, or Custodial Managers. These are the staff who monitor the wings and manage the day-to-day operation of the prison.

Non-uniformed staff are Prison Governors. These people manage the overall running of the prison including finance, programmes and procedures, and the prison’s overall development. Within any prison there can be many governors of various grades and specialties (e.g. operations, security, regimes, etc). They will report to a top-ranking governor often described as the “No.1 Governor”.

Service Providers also work within the prison, such as those who work within the chaplaincy, education department, in healthcare, or employment. Administrative staff will support the running of the prison more generally.