The prison system has failed in a "scandalous" way, with reoffending rates too high and shameful levels of violence, David Cameron will say today as he launches a sweeping programme of reform.
The Prime Minister will announce the creation of six "reform prisons" where governors are given greater control over the way their jails are run, along with measures to transform the education system behind bars.
Mr Cameron will insist that punishment is "not a dirty word" but prisoners must not be allowed to feel that society has given up on them.
In the speech, billed by Downing Street as the first focused purely on prisons by a British prime minister in more than two decades, Mr Cameron will commit to creating the new reform prisons by the end of the year.
He will accept the recommendations made in Dame Sally Coates' review of prison education, which will be published soon, including the end to regional contracts, and will also promise to protect the £130 million prison education budget.
Liberal Democrat former education minister David Laws will chair a new social enterprise and work with Dame Sally and organisations such as Teach First to develop a new scheme that will encourage graduates to work with offenders.
In a sign that he is moving Tory policy a long way from the "prison works" mantra of former leader Lord Howard, the Prime Minister will declare that penal reform should be the "great progressive cause in British politics".
But he will acknowledge in some cases there is no alternative to prison.
He will say: "My starting point is this: we need prisons. Some people - including, of course, rapists, murderers, child abusers, gang leaders - belong in them. For me, punishment - that deprivation of liberty - is not a dirty word.
"I never want us to forget that it is the victims of crime who should always be our principal priority. And I am not unrealistic or starry-eyed about what prisons can achieve.
"Not everyone shows remorse and not everyone seeks redemption.
"But I also strongly believe that we must offer chances to change; that for those trying hard to turn themselves around, we should offer hope; that in a compassionate country, we should help those who've made mistakes to find their way back onto the right path."
Prisoners should be viewed out "potential assets to be harnessed" but "the failure of our system today is scandalous".
In the speech in London he will highlight figures showing 46% of all prisoners reoffend within a year of release, rising to 60% for those who served short sentences.
Mr Cameron will acknowledged that "current levels of prison violence, drug-taking and self-harm should shame us all", with a typical week seeing 600 incidents of self-harm, at least one suicide and 350 assaults including 90 on staff.
The cycle of reoffending costs up to £13 billion a year and leads to more victims of crime, he will say.
"It matters to you: because in the end, who are the victims of this re-offending? It's the mother who gets burgled or the young boy who gets mugged. It matters to the prison staff - some of the most deeply committed public servants in our country - who have to work in dangerous and intimidating conditions.
"And yes, it matters to the prisoners themselves, who mustn't feel like society has totally given up on them.
"I'm clear: we need wholesale reform. And I am convinced that with the right agenda, we can be world leaders in change just like we have been in welfare, just like in education we can demonstrate that with the right reforms, we can make a lasting difference to people in our society."
The Prime Minister has already announced plans to find alternatives to custody for pregnant women or new mothers and confirmed that a pilot scheme to track offenders by satellite will launch later this year.
He will also announce a drive to make our prisons more transparent in terms of how they operate allowing comparisons between different jails.
Frances Crook, chief executive of the Howard League for Penal Reform, said: "The Prime Minister is right to say that we do need prisons, and right to say that we don't need prisons as they are today.
"Prisons are currently violent and overcrowded. As such, they fail everyone: victims, the public, staff and prisoners themselves.
"Prison reform, however, is the tip of the iceberg. Improved education and increased autonomy for governors will not work if there are people crammed into filthy institutions with no staff to open the cell doors.
"We need action now to tackle sentence inflation and the profligate use of prison. Then the Prime Minister's vision can become a reality."