Chrissie Sneddon was the neighbour from hell. The 23-year-old single mother, lonely after splitting with the father of her five-year-old daughter, had been befriended by a gang of youths in her Dundee housing estate. In no time they turned her flat into little more than a gang hut.

Mayhem ensued. The high-rise block Sneddon lived in was repeatedly vandalised, with doors hauled off their hinges. Walls were sprayed with graffiti and every night was party night, with teenagers revelling until daybreak.

Such was Sneddon’s ignorance of decent neighbourly behaviour, she was unable to grasp anything was wrong. “They’re my friends,” she would shrug when confronted with evidence of vandalism. When she needed peace and quiet, she simply left the flat.

Sneddon’s lifestyle was an example of the lack of respect that Tony Blair, the prime minister, has highlighted as one of the failings of 21st-century Britain. All the more remarkable then that, after taking part in a ground-breaking social experiment, Sneddon is being praised by Blair as a shining example of a dream citizen.

After constant complaints to the police and Dundee city council’s housing department, Sneddon had been on the brink of eviction. It seemed likely her daughter, Leanne, would be taken into care. It was then she came into contact with NCH’s Dundee Families Project, which meant moving into a block of flats known locally as “Colditz”.

Offering intense 24-hour support from trained social workers, the project has won international praise. It represents a last chance for families showing the worst symptoms of dysfunctional parenting, substance abuse or antisocial behaviour. In fact, the regime bears comparison with the television show Supernanny, in which a trained childminder gives advice to hapless parents.

In Dundee, the supernanny is financed not by a television production company, but by the state. Praised by Blair as a beacon of excellence, the families project is about to become the model for a new Home Office scheme in England, in which on-site social workers will teach chaotic families everything from basic hygiene to how to cook a nutritious meal.

The need to get to problem parents before their children are harmed or spiral into criminality has never been clearer. The country was horrified last month when details emerged of the murder of Inverness girl Danielle Reid, 5, at the hands of Lee Gaytor, her mother’s partner. Her death could have been avoided, said a report, if agencies had kept a more co-ordinated eye on the family. And it emerged last week that two-year-old Derek Doran, of East Lothian, died after drinking the heroin substitute methadone, which had been prescribed to both his parents.

It was also recently revealed that a 15-year-old Edinburgh boy had broken an antisocial behaviour order imposed after he committed an estimated 800 offences in the city.

So, can the Dundee Families Project really turn a family like the Gallaghers from the television series Shameless into the squeaky-clean Waltons? With the cost of looking after just one family within the scheme estimated at £1,353 a week, is it an effective use of taxpayers’ money? And can its success really be replicated, as Blair hopes, all over the UK?

THE block of flats at 7 St Clement’s Terrace is grim-looking, but no more so than other blocks in the St Mary’s area of Dundee. Its brown-harled walls have seen better days and the metal fence makes the Colditz tag understandable. But the fence is standard issue for local authority housing in this area, and the steel cage around the CCTV camera is there, say staff, to protect it from pigeons, not vandals.

Inside the close, a register hangs on the wall — all adults must sign in and out of the building. The flats themselves are basic two-bedroom apartments. In the offices downstairs, bed sheets are drying in front of a radiator for the next social worker who will occupy an on-call bedroom. The balconies, strewn with children’s bikes, are hemmed in with wire mesh to prevent accidents.

The time Chrissie Sneddon and her daughter Leanne spent here changed their lives. “She lived here for a year,” says John Wallace, the project’s deputy manager. “Chrissie learnt about her rights as a tenant but also her responsibility to others.”

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