The IT industry's annual Byte Night fundraising sleep-out is celebrating is 10th anniversary this year.
Byte Night has raised over £1.5m for National Children's Homes (NCH) in its nine-year history.
The event sees senior figures from top technology companies sleep on the street for a night to highlight the problem of youth homelessness and improve services for young people leaving care.
The organisers raised an impressive £340,000 last year, and have set an ambitious target of £500,000 for this year's event on 3 October.
The main event will be held in London's Potters Field in the shadow of Tower Bridge, and other sleep outs will take place in cities across the UK.
The event is led by founding Byte Night members James Bennet, a director at Ernst & Young, and Ken Deeks, director of The Amber Group.
Celebrities and political figures are expected to attend, as well as representatives from IT giants such as HP, Dell and BT.
"When Byte Night first began 10 years ago, 35 people slept out for the night. This number has grown year-on-year, and we have now seen over 1,500 senior IT figures give up their bed for a night," said Deeks.
"I am incredibly proud of the way this campaign has generated awareness of youth homelessness and raised hundreds of thousands of pounds for NCH.
"We are lucky to be supported by such an impressive list of names from the technology elite, and I am honoured to be part of a team that continues to grow, develop and inspire."
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