A scheme that will see drug addicts given daily doses of medical-grade heroin will begin on Monday.
Costing £12,000 per person, the scheme in Middlesbrough, on Teesside, will see people take diamorphine twice a day under medical supervision.
The Heroin Assisted Treatment facility was announced last September but organisers said they had only recently secured the necessary licences.
Critics have said the scheme would perpetuate addiction.
Danny Ahmed, of Foundations Medical Practice which will host the clinic, said: "This treatment and recovery pilot is aimed at those for whom all other current methods have failed.
"This removes the constant need to commit crime in order to fund street heroin addiction."
Fifteen people have been selected to take part in the scheme.
It has been part-funded by Police and Crime Commissioner for Cleveland, Barry Coppinger, with further money provided by Durham Tees Valley Community Rehabilitation Company and the Tees and Wear Prisons Group.
Organisers said the costs would be lower than the £800,000 police estimate of dealing with drug-related crime in the community.
Mr Coppinger described it as "a tremendous step forward".
"This is the right thing to do," he said.
"There's strong evidence it can save lives and reduce harm, and we can't put a monetary value on that."
When the plan was announced last year, campaign group Europe Against Drugs said it "perpetuates addicts' maintenance on the drug when the goal should always be abstinence".
Columnist and writer Peter Hitchens said drug users were criminals and should not be treated as people with an illness.