The governor of Brixton Prison has said too many people are being locked up in London and not enough is done to curb re-offending.
Mr Podmore says too many offenders end up in prison
John Podmore told BBC News coping with overcrowding was putting pressure on the south London jail.
Too often offenders are sent to prison because there is nowhere else for them to go, he said.
He believes those with drug or mental health problems could be dealt with better in the community.
'Out of business'
"At the moment there's this never-ending cycle of re-offending, coming back into prison, and there are guys here who will seek to come here for a whole variety of reasons.
"If you've got a drug problem you want detox - you come in here, you'll get detox tonight," he told BBC News.
He said such support was more difficult to find out in the wider community and urged authorities to find new ways of dealing with less dangerous offenders.
"Everyone is going to go back into the communities they came from... I'm a part of that community, and I've got to work with that community," he said.
"Ironically, I want to go out of business. I'm a £20m business in south London, I want to go out of business."
In 2004, the chief inspector of prisons ruled overcrowding was hampering improvements at Brixton Prison.
Basic needs such as pillows, privacy and cleanliness were not being met, the report said.