Yet some of the most hardened, drug-dependent inmates in HMP Coldingley have found that by confiding their darkest secrets in each other they have been able to see their way to a brighter future.
For those acclimatised to an environment where any signals of weakness are seized upon and ruthlessly exploited, the idea of group therapy is a culture shock which, in their words, "takes a lot of bottle".
Trevor, who is in the eighth year of a life sentence for a drug-related murder, said: "It has helped me get in touch with who I am; my feelings, my emotions and why I turned to drugs in the first place.
"I've discovered so much about myself personally." His enthusiasm for the programme - run by the Rehabilitation for Addicted Prisoners Trust (RAPt) - is all the greater for having approached it with deep cynicism. He had already tried other drug-rehabilitation courses in other jails and failed them. "It was learning from textbooks and being talked to by people who didn't know how I was feeling," he explained.
"Here even the counsellors have had experiences. It helps to know that I am talking to fellow addicts."
Almost all RAPt staff have experienced drug problems and prisoners who have passed through the programme often stay on as "peer supporters" to help fellow inmates. Partly thanks to the RAPt scheme, Coldingley prison has reduced the number of inmates testing positive for drugs from 40 per cent to 15 per cent in the space of a year. The number testing positive for opiates has fallen from 3.8 per cent to 2.6 per cent in the same period.
It is a signal of hope after widely expressed fears that drug use had become so rife in Britain's jails that even prisoners who began their sentences without an addiction would have one by the time they were released. Yesterday the Government announced the new Prison Service Drugs Strategy with the promise that treatment programmes would be greatly expanded.
Richard Tilt, director-general of the Prison Service, conceded that he was dependent on the Government's comprehensive spending review, which will be completed later this summer, for the money to allow the programmes to be set up.
Adam Sampson, chief executive of RAPt, said at least pounds 10m a year on top of the current annual spend of pounds 7m was needed to set up the necessary new schemes.
He said: "Unless government supports these fine words with some hard cash, their good intentions will all be wasted."
At the launch of the strategy George Howarth, the drugs minister, said that a decision to reduce punishments for the use of cannabis in prison was not a signal that the Government condoned the use of soft drugs.
He said the measure, which was revealed in The Independent last weekend, brought the penalties for cannabis use in jails into line with those applied to the wider public. "I am not suggesting here that we condone the use of certain drugs but that we pay particular attention to those drugs that cause the most damage," he said.
John Smith, the governor at Coldingley, said he was trying to bring about a cultural change in the prison. "A few years ago, newly admitted prisoners were expected to use drugs and it was not all right for them to say they didn't take them," he said.
"There is a real push in this regime to provide a positive culture based on individual responsibility, hard work and leading to a useful life on release."
The change has enabled the Surrey jail to reduce its level of mandatory drug tests and concentrate on a voluntary scheme in which nearly all inmates take part to show they are drug-free. This enables the jail to focus more intently on those who are not.
The success of the RAPt scheme, a 12-week programme based on the principles of Narcotics Anonymous, demanding total abstinence from drugs while providing a full daily routine, is based on its interaction with other drug programmes inside the jail.
The Acorn project runs an outreach service where drug advice workers operate as if they were in the outside world, helping to ensure that RAPt graduates do not relapse.
More open-minded prisoners are encouraged to participate in complementary medicine, including acupuncture and cranial osteopathy, to address their anger and develop their self-awareness.
All of which seems to have helped reduce tension within the jail. In the time that positive drug tests have plummeted, the number of disciplinary incidents in the prison has fallen by 60 per cent.Reuse content