More than 800 guests raised a record £600,000 at the annual Norwood property lunch last Friday.
Guest speaker broadcaster Andrew Marr spoke about the importance of the "third sector", a term used by Prime Minister David Cameron to refer to voluntary organisations.
Praising the guests at the fundraiser, he added: "You are all busy, hardworking people who have chosen to put some time and some money aside to help other people.
"I know in some ways this is a big property event, and in other ways, a big Jewish community event - but I suggest to you it is a very typical British event.
"The British at our best; all of us, at our best. Our busy, hardworking people, who put time and money aside to help those less fortunate than ourselves."
Addressing the guests Martha Lomanto spoke about how Norwood's Ravenswood centre had helped her sons: 38-year-old Guiseppe, who has epilepsy and a learning disability, and Lawrence, 36, who has severe autism.
Mrs Lomanto, from Ilford in Essex, spoke movingly about how her sons had moved to the Ravenswood village five years ago.
"To everyone that knows them, they will always be 'the boys'," noting that they had attended the charity's clubs and schemes from a young age.
"In 2009, we received a phone call that would go on to secure their future. The future of the boys was always the elephant in the room. We knew it was something that had to be dealt with, but equally we didn't want to think about it. That phone call changed that."
After being told that living opportunities were available, she said: "I knew it was the right place for the boys. Five years on we have not been let down.
"They are happy, part of the community and they belong."
Elaine Kerr, chief executive of Norwood, said: "We are operating in one of the most challenging and unpredictable economies we have ever experienced. People depend on us, often for all of their lives, but the reality is that we simply cannot meet their needs without your incredible support."
Funds raised at the cental London event will go towards the charity's projects for vulnerable people with learning difficulties.