By Andy Dangerfield
BBC News, London
In the winter of 1969, a vicar opened the basement of his church in central London's Soho as a temporary night shelter for the homeless.
Vicar Ken Leech, set up Centrpoint in 1969 with just £30 in the bank
Forty years on, as its drive to help the young homeless over Christmas gets under way, Centrepoint looks very different.
The charity, which celebrates its 40th anniversary this week, has helped more than 73,000 homeless 16 to 25-year-olds.
And it provides far more than a bed for the 825 young people it works with across London and the north east of England each day.
But Centrepoint has had to adapt as the issues facing homeless people have changed over time.
Ken Leech, who had just £30 in the bank when he founded the charity, says he "wanted to do something for people who were vulnerable and not yet into drugs or prostitution".
'Paved with gold'
In 1970, Sandy Marks was one of the first people Centrepoint helped, when she was 16.
"A lot of homeless people came to London thinking the streets were paved with gold," she says.
"They thought you'd turn up, get a job and somewhere to live. They ended up, like me, sleeping in bushes."
Back then, Centrepoint offered homeless people shelter for up to three consecutive nights.
Sandy Marks was Mayor of Islington during the 1990s
"You got soup and a roll and had to leave early," she says.
"But it gave me respite to think about what the hell I was doing. In 1970, getting a job, a bedsit and back on your feet was easier."
Ms Marks, who was Mayor of Islington in 1996, says: "Now there are thousands of hostel places, but it's almost impossible to get somewhere to rent.
"The longer a person is homeless, the longer their own strength is destroyed. Projects that enable people to build self-esteem are invaluable."
Centrepoint's chief executive, Seyi Obakin, says homelessness affects young people "in a deeper, more chaotic way" than it used to.
"People we see don't have the emotional and social capital that many young people used to have," he says.
"They have more mental health and substance misuse issues and more numeracy and literacy problems."
About eight years ago, Centrepoint decided it needed to do far more than provide shelter and food for the night.
"We decided if we didn't do more, young people would come to us homeless, stay for a couple of years and be no better off."
Everyone who uses Centrepoint now has an action plan to develop in areas such as health, learning, finance, and engaging with society.
In 2003, Stephanie, from south east London, ran away from home aged 15.
"I was a young vulnerable lady on rough streets. I worried about where I would stay next and when I would eat," she says.
She says Centrepoint supported her through difficult times and offered emotional support as well as financial and career advice.
Stephanie enrolled on a course which enabled her to train new workers coming into the charity.
"This built my confidence and self-esteem," she says.
Jordan, whose parents were drug addicts, was helped by Centrepoint after leaving home in 2007, aged 17.
"You can talk to them if you're in trouble," he says. "They've helped me grow up."
Jordan joined the charity's football team, which he says "was useful in making friends", and he used Centrepoint's computers to write his CV, find work and access social groups.
Now, working in a superstore, he hopes to move into rented accommodation in the New Year.
Returning to Centrepoint 40 years after he founded the charity, Ken Leech says he is "proud but also depressed it's still needed".
"We thought that in 1969 that it was quite possible to make affordable housing available," he says.
Centrepoint chief Seyi Obakin says more housing stock is needed
Despite targets by London Mayor Boris Johnson to eradicate rough sleeping in the capital by 2012, official figures show a rise of 15% in 2008-9 compared to the previous year.
And with youth unemployment at its highest level in more than a decade, young people are at increased risk of becoming homeless.
But Mr Obakin thinks Mr Johnson's targets are realistic.
"It is possible to eradicate rough sleeping by 2012. But that's just one manifestation of homelessness," he says.
"We need more housing stock and more flexibility in rentals. Many homeless sleep on sofas or buses overnight."
Mr Obakin believes the charity will need to adapt as issues facing homeless people change.
"An issue facing young people now is how you get respect. We meet many people who are in gangs and carry weapons. But that's a current issue," he says.
Centrepoint founder Ken Leech returns to the charity after 40 years
Looking ahead, he predicts many challenges.
"As we come out of recession, we'll see more young homeless people who are addicted to substances, who are in gangs, or who have fallen out of education," he says.
A unified response between organisations is one approach that may help tackle young homelessness in the future
"When I look around we have pockets of initiative that tackle different parts of the problem but not always in the places they're needed, and often people don't even know about them," says Mr Obakin. We just need coherence."