How can this charity help homeless people regain their confidence?

Do you know the open-air art gallery in London's Blackall Street? Not many Londoners know it either, but Henri does and he is willing to show it to you.

Henri used to sleep rough until he met a charity that helps homeless people get back on their feet by becoming tour guides.

Rather than show traditional London sights, 'Unseen Tours' take people off the beaten track. Henri has been teaching tourists about the history and architecture of Shoreditch, where he slept on public benches for three years.

When he felt isolated, contact with the volunteer network 'The Sock Mob' gave Henri hope. "Not everyone just looked down on me," he said.

The tours aren't the only initiative to help those who have suffered a reversal of fortune to stand tall again.

An innovative college for homeless people in London, the first of its kind in the country, is attracting hundreds of students. The Recovery College, set up by St Mungo's charity, is providing courses designed to improve technical skills and life skills.

According to Andy Williams, who helps to organise the college, the most popular courses have proved to be about raising self-confidence and developing self-esteem.

Steve, now in his 50s, told BBC reporter Sean Coughlan how much of a difference it makes to "have a bit of confidence". He had dyslexia and drifted out of school when he was 12. Because Steve's problem was not recognised at the time he was "seen as an illiterate", and suffered with depression and alcohol abuse.

He says the status of 'student' is itself important for people who are used to being treated as outcasts.

Some charities aim not only to empower the homeless but also to make them popular. The Homeless World Cup started ten years ago. Today the tournament draws teams from 48 countries made up of players - men and women - who are, or have been, living in the streets. It gives them a chance to become heroes on the pitch.