This Christmas, as it has done for the past 35 years, Crisis will open its doors to thousands of homeless people who have nowhere else to go.
But for the first time people will have the choice of visiting one of seven centres that most suits their needs. There will be sites in north, south, east and west London, as well as specialist centres, including one for women only.
"We want people to be much nearer to services in their local areas so they can access them more effectively after Christmas," explains Leslie Morphy, the new chief executive of Crisis.
Providing Christmas dinner and entertainment for up to 2,000 people is a logistical nightmare, she says. The charity aims to recruit 5,000 volunteers and currently has 4,000, which is better than average for this time of the year.
"The ratio of volunteers to staff is high because we want volunteers to have time to talk to the clients and not just hand out food," she says.
"We also try to stop people from taking on too many shifts - it can be exhausting, and we want them to be able to enjoy the experience."
Despite the charity's origins (it used to be called Crisis at Christmas), there is more to it than seasonal work. Crisis has developed a broad range of services to help homeless people get their lives back on track. Many of these services are run from the organisation's Skylight centre, which is based in the same building as its head office near London's trendy Spitalfields market. Skylight services reflect the holistic approach introduced by Morphy's predecessor, Shaks Ghosh.
"It's not just about putting a roof over someone's head," explains Morphy.
"Homeless people have a whole range of needs and problems - you can't solve anything by focusing only on one narrow area."
Fifteen months ago Crisis introduced the Skylight Cafe, which is run as a social enterprise and staffed by clients. The charity hopes to replicate the success of Skylight's cafe and centre in other areas, initially at a new site in Newcastle.
The Spitalfields building is chaotic, with people constantly coming in and going out, but a friendly buzz gives it the air of a close-knit community.
Staff and clients rub shoulders and know each other by name.
Morphy says: "The environment is very important for people who have lived in dire circumstances for so long. The contact with our members keeps us close to what we are doing and makes us more aware of how to tailor services to them."
The charity is also leading a coalition of 32 adult learning and voluntary sector organisations in lobbying the Government to make adult education courses more accessible.
Morphy says: "One of the reasons Crisis interested me is that, as well as developing effective services, it also has a record for campaigning, which is unusual. Campaigning is not just about being anti-government; it's about bringing expertise to the agenda.
"Traditionally, we have received very little statutory funding, and I believe we should seek more. But you need to retain the ability to say to government that policies are not in the interests of homeless people, if they are not. And if that means not taking funding, then you don't take it."
Morphy's immediate plans include recruiting more volunteers to work throughout the year. Given the popularity of Crisis's Christmas operation, she is likely to be successful.
She says: "People volunteer with us because it's a revelation that changes volunteers' lives as much as it changes clients' lives. We recognise that volunteers have to get something out of the experience, too. Old-fashioned do-gooding isn't enough."