BBC Radio and television will link up on Friday to try to raise more than £2m for children in need.
Stars and celebrities will be on BBC 1, the four national radio networks and local radio stations during an evening of phone-in programmes to receive the listeners and viewers' donations and pledges for the children.
Last year, the BBC raised £1m with a similar radio/telethon. Wrestler Big Daddy, one of the celebrities who will be appearing, said today: "Our aim is to double last year's figure and try to raise at least £2m for the kids. It's a wonderful cause."
Pop singers Kim Wilde, Lulu and Adam Ant will also be among the stars taking part, who include Terry Wogan, Gloria Hunniford, James Hunt, Petula Clark, andy Peebles and Chris Serle. Kim and Big Daddy were at the BBC this morning to announce this year's appeal. With them, to say "thank you", were four children from a special school in Wimbledon, South London, who enjoyed a summer holiday at a school camp, paid for from last year's appeal, which helped thousands of other children in need.