By Emma Griffiths
BBC News Online, London
Drop in at the 999 Club in south-east London and you might notice a wiry 68-year-old in a baseball cap and bomber jacket.
Jim Lee spends his days on buses or at the 999 Club
Jim Lee is a familiar face to volunteers at the centre on Deptford Broadway, where he has a cup of tea before he "disappears", travelling on buses across London for most of the day.
But in the eyes of the state, Jim is an invisible man.
Born to a family of travellers in a field in Kent, his birth was never registered, he was disowned by his mother and supported himself from the age of 14.
While other children were at school, Jim was working on markets and, as he got older, labouring in fields and on building sites.
He had no need of official papers and says he never had a National Insurance (NI) number because he never needed one.
But in recent years, new legislation has tightened up employment on building sites and Jim has found it harder to find work.
When his job came to an end last year, Jim, who is now carrying a leg injury, could not find work, could not pay his rent and started sleeping at New Cross bus garage.
Without being able to prove his identity, it has proved difficult to get access to the services designed to help the homeless.
Lewisham Council says it has to assess whether people are eligible for help under the Housing Act 1996.
But Jim has never claimed benefits before and has no papers to prove who he is - his life's possessions fit in two laundry bags.
"He's basically never been in 'the system'," said Adrian Spalding, administrator of the 999 Club which has been trying to help Jim.
"From the moment he was born he has had no paper work attached to him.
"You can see him and touch him but he can't prove who he is. According to the state, he doesn't exist."
The council says Jim's is an "extremely rare" case but agreed to temporarily house him after some campaigning by the 999 Club.
But it was provided on the basis he would be issued with a permanent NI number by the Department of Work and Pensions (DWP) to claim pension credit and housing benefit.
After pressure from the 999 Club and local MP, the DWP has issued a temporary number and an interim payment, administered by the club on Jim's behalf.
But eight months after Jim first came to them, the club fears he will never get a permanent NI number because he cannot prove his identity.
Then, they say, it is only a matter of time before he is back on the streets.
The DWP says it does issue numbers to people with no documentation, if they can prove their identity through another way - such as getting evidence from a relative or acquaintance.
But Jim cannot remember his family and has spent his life moving around.
Lewisham residents work at the 999 Club offering informal help
A DWP spokesman said: "He has basically not been contributing anything for his entire working life. He has effectively been working for the black economy.
"It's something we have to guard against because we get a lot of people who use false NI numbers - there is a lot of fraud around."
Back at the 999 Club, Mr Spalding accepts some people will ask why Jim should benefit now, when he has never paid taxes or NI contributions.
"He's still a person, he's still a human being. If you accept you only get out what you pay in, he might just as well go and cut his wrists now," said Mr Spalding.
"Society should care for all people within our society, whatever their circumstances."
Lewisham Council says it will nominate Jim for permanent re-housing if he gets an NI number.