A senior police officer recently revived the phrase - until now associated with Michael Howard when home secretary - Prison Works.
In fact, imprisonment has two main purposes. First, containment so offenders are physically restrained from committing more crimes for a fixed period. Second, reducing crime by sending back to the community people who can lead what the Prison Service used to call "a good and useful life".
Prison conspicuously fails to work on the second count: 60 per cent of those jailed are reconvicted within two years. Two-thirds of those in prison have been there before.
Offenders bring many problems with them into the prison system. Very high proportions have experienced family breakdown, been in care, run away from home, or have mental health or drug and alcohol dependency problems.
Many will have walked away or been excluded from education quite early in their secondary career.
It is estimated that 60 per cent of prisoners have poor literacy and communication skills and 75 per cent poor numeracy skills. Forty- nine per cent of men and 71 per cent of women in prison have no qualifications.
There is no doubt that most offenders fall squarely in the groups targeted by further education for widening participation.
In a discussion paper for the National Institute for Adult Continuing Education, I argue that, for prisoners, in the words of Helena Kennedy's groundbreaking report, Learning Works.
Research, tells us factors that discourage re-offending include a place to live, family contact, being clear of drug dependence and having a job.
Education and training in prisons clearly has a role, along with services like probation, health and the chaplaincy, in providing prisoners with skills and understanding that will help them in all these areas. Yet 90 per cent of prisoners leave with no job to go to and only 6 per cent continue on the outside with any training begun in prison.
But much could be done to improve and expand education and training to meet employers' and society's needs.
Since 1997 there has been a switch away from what the Government called "recreational" activities in prisons and a concentration on a core curriculum of skills for work. This has in effect meant a concentration on basic skills often to the virtual exclusion of other educational activities.
A major problem is that "vocational" training in prisons does not come within the responsibilities of prison education managers and is separate from the core curriculum.
So, though since 1993 most contracts for education in prisons have been held by FE colleges, they have not been responsible for what many people still regard as their core activity - the delivery of accredited vocational skills aligned where possible with labour market need.
It has also meant that while ministers have been announcing large and welcome increases in spending on prison education, the volume of vocational training has actually been shrinking (by as much as 50 per cent over the past five years) as governors turn workshops over to production so that prison industries can meet their income targets.
The lack of any strategy for vocational training and of any policy for the recruitment, retention and training of instructors has led to a widening gap between what is done in prisons and mainstream FE.
But we at NIACE argue that there is light at the end of the tunnel.The new Prisoners Learning and Skills Unit at Department for Education and Skills, which has access to the policy-making machine, seems not only to understand the issues but to be determined to grasp the nettle.
It is committed to establishing continuity between custody and community; to a proper assessment of prisoners' prior achievement and needs so each can have a learning plan that makes sense to them.
If the unit can make good on those commitments we may see education and training at last making its proper contribution to the reduction of offending. Learning works!
Tony Uden is senior research fellow at NIACE